virsh (1)

Leading comments

Automatically generated by Pod::Man 4.09 (Pod::Simple 3.35)

Standard preamble:
========================================================================

(The comments found at the beginning of the groff file "man1/virsh.1".)

NAME

virsh - management user interface

SYNOPSIS

virsh []... []

virsh [

]... []...

DESCRIPTION

The virsh program is the main interface for managing virsh guest domains. The program can be used to create, pause, and shutdown domains. It can also be used to list current domains. Libvirt is a C toolkit to interact with the virtualization capabilities of recent versions of Linux (and other OSes). It is free software available under the Lesser General Public License. Virtualization of the Linux Operating System means the ability to run multiple instances of Operating Systems concurrently on a single hardware system where the basic resources are driven by a Linux instance. The library aims at providing a long term stable C It currently supports Xen, OpenVZ, VirtualBox and VMware

The basic structure of most virsh usage is:

  virsh [OPTION]... <command> <domain> [ARG]...

Where command is one of the commands listed below; domain is the numeric domain id, or the domain name, or the domain

; and are command specific options. There are a few exceptions to this rule in the cases where the command in question acts on all domains, the entire machine, or directly on the xen hypervisor. Those exceptions will be clear for each of those commands. Note: it is permissible to give numeric names to domains, however, doing so will result in a domain that can only be identified by domain id. In other words, if a numeric value is supplied it will be interpreted as a domain id, not as a name.

The virsh program can be used either to run one

by giving the command and its arguments on the shell command line, or a which is a single shell argument consisting of multiple actions and their arguments joined with whitespace, and separated by semicolons between commands. Within , virsh understands the same single, double, and backslash escapes as the shell, although you must add another layer of shell escaping in creating the single shell argument. If no command is given in the command line, virsh will then start a minimal interpreter waiting for your commands, and the quit command will then exit the program.

The virsh program understands the following

.

-c, --connect

URI

Connect to the specified

URI

, as if by the connect command, instead of the default connection.

-d, --debug

LEVEL

Enable debug messages at integer

LEVEL

and above.

LEVEL

can range from 0 to 4 (default). See the documentation of

VIRSH_DEBUG

environment variable below for the description of each

LEVEL

.

-e, --escape string

Set alternative escape sequence for console command. By default, telnet's ^] is used. Allowed characters when using hat notation are: alphabetic character, @, [, ], \, ^, _.

-h, --help

Ignore all other arguments, and behave as if the help command were given instead.

-k, --keepalive-interval

INTERVAL

Set an

INTERVAL

(in seconds) for sending keepalive messages to check whether connection to the server is still alive. Setting the interval to 0 disables client keepalive mechanism.

-K, --keepalive-count

COUNT

Set a number of times keepalive message can be sent without getting an answer from the server without marking the connection dead. There is no effect to this setting in case the

INTERVAL

is set to 0.

-l, --log

FILE

Output logging details to

FILE

.

-q, --quiet

Avoid extra informational messages.

-r, --readonly

Make the initial connection read-only, as if by the --readonly option of the connect command.

-t, --timing

Output elapsed time information for each command.

-v, --version[=short]

Ignore all other arguments, and prints the version of the libvirt library virsh is coming from

-V, --version=long

Ignore all other arguments, and prints the version of the libvirt library virsh is coming from and which options and driver are compiled in.

NOTES

Most virsh operations rely upon the libvirt library being able to connect to an already running libvirtd service. This can usually be done using the command invoke-rc.d libvirtd start.

Most virsh commands require root privileges to run due to the communications channels used to talk to the hypervisor. Running as non root will return an error.

Most virsh commands act synchronously, except maybe shutdown, setvcpus and setmem. In those cases the fact that the virsh program returned, may not mean the action is complete and you must poll periodically to detect that the guest completed the operation.

virsh strives for backward compatibility. Although the help command only lists the preferred usage of a command, if an older version of virsh supported an alternate spelling of a command or option (such as --tunnelled instead of --tunneled), then scripts using that older spelling will continue to work.

Several virsh commands take an optionally scaled integer; if no scale is provided, then the default is listed in the command (for historical reasons, some commands default to bytes, while other commands default to kibibytes). The following case-insensitive suffixes can be used to select a specific scale:
  b, byte  byte      1
  

       kilobyte  1,000
  k, KiB   kibibyte  1,024
         megabyte  1,000,000
  M, MiB   mebibyte  1,048,576
         gigabyte  1,000,000,000
  G, GiB   gibibyte  1,073,741,824
         terabyte  1,000,000,000,000
  T, TiB   tebibyte  1,099,511,627,776
         petabyte  1,000,000,000,000,000
  P, PiB   pebibyte  1,125,899,906,842,624
         exabyte   1,000,000,000,000,000,000
  E, EiB   exbibyte  1,152,921,504,606,846,976

GENERIC COMMANDS

The following commands are generic i.e. not specific to a domain.

help [command-or-group]

This lists each of the virsh commands. When used without options, all commands are listed, one per line, grouped into related categories, displaying the keyword for each group.

To display only commands for a specific group, give the keyword for that group as an option. For example:

 virsh # help host

  Host and Hypervisor (help keyword 'host'):
     capabilities                   capabilities
     cpu-models                     show the CPU models for an architecture
     connect                        (re)connect to hypervisor
     freecell                       NUMA free memory
     hostname                       print the hypervisor hostname
     qemu-attach                    Attach to existing QEMU process
     qemu-monitor-command           QEMU Monitor Command
     qemu-agent-command             QEMU Guest Agent Command
     sysinfo                        print the hypervisor sysinfo
     uri                            print the hypervisor canonical URI

To display detailed information for a specific command, give its name as the option instead. For example:

 virsh # help list
   NAME
     list - list domains

   SYNOPSIS
     list [--inactive] [--all]

   DESCRIPTION
     Returns list of domains.

   OPTIONS
     --inactive       list inactive domains
     --all            list inactive & active domains

quit, exit

quit this interactive terminal

version [--daemon]

Will print out the major version info about what this built from. If --daemon is specified then the version of the libvirt daemon is included in the output.

Example

 $ virsh version
 Compiled against library: libvirt 1.2.3
 Using library: libvirt 1.2.3
 Using API: QEMU 1.2.3
 Running hypervisor: QEMU 2.0.50

 $ virsh version --daemon
 Compiled against library: libvirt 1.2.3
 Using library: libvirt 1.2.3
 Using API: QEMU 1.2.3
 Running hypervisor: QEMU 2.0.50
 Running against daemon: 1.2.6

cd [directory]

Will change current directory to directory. The default directory for the cd command is the home directory or, if there is no

HOME

variable in the environment, the root directory.

This command is only available in interactive mode.

pwd

Will print the current directory.

connect [

URI

] [--readonly]

(Re)-Connect to the hypervisor. When the shell is first started, this is automatically run with the

URI

parameter requested by the "-c" option on the command line. The

URI

parameter specifies how to connect to the hypervisor. The documentation page at <libvirt.org/uri.html> list the values supported, but the most common are:

xen:///

this is used to connect to the local Xen hypervisor

qemu:///system

connect locally as root to the daemon supervising

QEMU

and

KVM

domains

qemu:///session

connect locally as a normal user to his own set of

QEMU

and

KVM

domains

lxc:///

connect to a local linux container

To find the currently used

URI,

check the uri command documented below.

For remote access see the documentation page at <libvirt.org/uri.html> on how to make URIs. The --readonly option allows for read-only connection

uri

Prints the hypervisor canonical

URI,

can be useful in shell mode.

hostname

Print the hypervisor hostname.

sysinfo

Print the

XML

representation of the hypervisor sysinfo, if available.

nodeinfo

Returns basic information about the node, like number and type of

CPU,

and size of the physical memory. The output corresponds to virNodeInfo structure. Specifically, the ``

CPU

socket(s)'' field means number of

CPU

sockets per

NUMA

cell. The information libvirt displays is dependent upon what each architecture may provide.

nodecpumap [--pretty]

Displays the node's total number of CPUs, the number of online CPUs and the list of online CPUs.

With --pretty the online CPUs are printed as a range instead of a list.

nodecpustats [cpu] [--percent]

Returns cpu stats of the node. If cpu is specified, this will print the specified cpu statistics only. If --percent is specified, this will print the percentage of each kind of cpu statistics during 1 second.

nodememstats [cell]

Returns memory stats of the node. If cell is specified, this will print the specified cell statistics only.

nodesuspend [target] [duration]

Puts the node (host machine) into a system-wide sleep state and schedule the node's Real-Time-Clock interrupt to resume the node after the time duration specified by duration is out. target specifies the state to which the host will be suspended to, it can be ``mem'' (suspend to

RAM

), ``disk'' (suspend to disk), or ``hybrid'' (suspend to both

RAM

and disk). duration specifies the time duration in seconds for which the host has to be suspended, it should be at least 60 seconds.

node-memory-tune [shm-pages-to-scan] [shm-sleep-millisecs] [shm-merge-across-nodes]

Allows you to display or set the node memory parameters. shm-pages-to-scan can be used to set the number of pages to scan before the shared memory service goes to sleep; shm-sleep-millisecs can be used to set the number of millisecs the shared memory service should sleep before next scan; shm-merge-across-nodes specifies if pages from different numa nodes can be merged. When set to 0, only pages which physically reside in the memory area of same

NUMA

node can be merged. When set to 1, pages from all nodes can be merged. Default to 1.

Note: Currently the ``shared memory service'' only means

KSM

(Kernel Samepage Merging).

capabilities

Print an

XML

document describing the capabilities of the hypervisor we are currently connected to. This includes a section on the host capabilities in terms of

CPU

and features, and a set of description for each kind of guest which can be virtualized. For a more complete description see:
  <libvirt.org/formatcaps.html> The

XML

also show the

NUMA

topology information if available.

domcapabilities [virttype] [emulatorbin] [arch] [machine]

Print an

XML

document describing the domain capabilities for the hypervisor we are connected to using information either sourced from an existing domain or taken from the virsh capabilities output. This may be useful if you intend to create a new domain and are curious if for instance it could make use of

VFIO

by creating a domain for the hypervisor with a specific emulator and architecture.

Each hypervisor will have different requirements regarding which options are required and which are optional. A hypervisor can support providing a default value for any of the options.

The virttype option specifies the virtualization type used. The value to be used is either from the 'type' attribute of the <domain/> top level element from the domain

XML

or the 'type' attribute found within each <guest/> element from the virsh capabilities output. The emulatorbin option specifies the path to the emulator. The value to be used is either the <emulator> element in the domain

XML

or the virsh capabilities output. The arch option specifies the architecture to be used for the domain. The value to be used is either the ``arch'' attribute from the domain's

XML

<os/> element and <type/> subelement or the ``name'' attribute of an <arch/> element from the virsh capabililites output. The machine specifies the machine type for the emulator. The value to be used is either the ``machine'' attribute from the domain's

XML

<os/> element and <type/> subelement or one from a list of machines from the virsh capabilities output for a specific architecture and domain type.

For the qemu hypervisor, a virttype of either 'qemu' or 'kvm' must be supplied along with either the emulatorbin or arch in order to generate output for the default machine. Supplying a machine value will generate output for the specific machine.

inject-nmi domain

Inject

NMI

to the guest.

list [--inactive | --all] [--managed-save] [--title] { [--table] | --name | --uuid } [--persistent] [--transient] [--with-managed-save] [--without-managed-save] [--autostart] [--no-autostart] [--with-snapshot] [--without-snapshot] [--state-running] [--state-paused] [--state-shutoff] [--state-other]

Prints information about existing domains. If no options are specified it prints out information about running domains.

An example format for the list is as follows:

virsh list
  Id    Name                           State
 ----------------------------------------------------
  0     Domain-0                       running
  2     fedora                         paused

Name is the name of the domain.

ID

the domain numeric id. State is the run state (see below).

STATES

The State field lists what state each domain is currently in. A domain can be in one of the following possible states:

running

The domain is currently running on a

CPU

idle

The domain is idle, and not running or runnable. This can be caused because the domain is waiting on

IO

(a traditional wait state) or has gone to sleep because there was nothing else for it to do.

paused

The domain has been paused, usually occurring through the administrator running virsh suspend. When in a paused state the domain will still consume allocated resources like memory, but will not be eligible for scheduling by the hypervisor.

in shutdown

The domain is in the process of shutting down, i.e. the guest operating system has been notified and should be in the process of stopping its operations gracefully.

shut off

The domain is not running. Usually this indicates the domain has been shut down completely, or has not been started.

crashed

The domain has crashed, which is always a violent ending. Usually this state can only occur if the domain has been configured not to restart on crash.

pmsuspended

The domain has been suspended by guest power management, e.g. entered into s3 state.

Normally only active domains are listed. To list inactive domains specify --inactive or --all to list both active and inactive domains.

To further filter the list of domains you may specify one or more of filtering flags supported by the list command. These flags are grouped by function. Specifying one or more flags from a group enables the filter group. Note that some combinations of flags may yield no results. Supported filtering flags and groups:

Persistence

Flag --persistent is used to include persistent domains in the returned list. To include transient domains specify --transient.

Existence of managed save image

To list domains having a managed save image specify flag --with-managed-save. For domains that don't have a managed save image specify --without-managed-save.

Domain state

The following filter flags select a domain by its state: --state-running for running domains, --state-paused for paused domains, --state-shutoff for turned off domains and --state-other for all other states as a fallback.

Autostarting domains

To list autostarting domains use the flag --autostart. To list domains with this feature disabled use --no-autostart.

Snapshot existence

Domains that have snapshot images can be listed using flag --with-snapshot, domains without a snapshot --without-snapshot.

When talking to older servers, this command is forced to use a series of

API

calls with an inherent race, where a domain might not be listed or might appear more than once if it changed state between calls while the list was being collected. Newer servers do not have this problem.

If --managed-save is specified, then domains that have managed save state (only possible if they are in the shut off state, so you need to specify --inactive or --all to actually list them) will instead show as saved in the listing. This flag is usable only with the default --table output. Note that this flag does not filter the list of domains.

If --name is specified, domain names are printed instead of the table formatted one per line. If --uuid is specified domain's

UUID

's are printed instead of names. Flag --table specifies that the legacy table-formatted output should be used. This is the default.

If both --name and --uuid are specified, domain

UUID

's and names are printed side by side without any header. Flag --table specifies that the legacy table-formatted output should be used. This is the default if neither --name nor --uuid are specified. Option --table is mutually exclusive with options --uuid and --name.

If --title is specified, then the short domain description (title) is printed in an extra column. This flag is usable only with the default --table output.

Example:

virsh list --title
  Id    Name                           State      Title
 --------------------------------------------------------------------------
  0     Domain-0                       running    Mailserver 1
  2     fedora                         paused

freecell [{ [--cellno] cellno | --all }]

Prints the available amount of memory on the machine or within a

NUMA

cell. The freecell command can provide one of three different displays of available memory on the machine depending on the options specified. With no options, it displays the total free memory on the machine. With the --all option, it displays the free memory in each cell and the total free memory on the machine. Finally, with a numeric argument or with --cellno plus a cell number it will display the free memory for the specified cell only.

freepages [{ [--cellno] cellno [--pagesize] pagesize | --all }]

Prints the available amount of pages within a

NUMA

cell. cellno refers to the

NUMA

cell you're interested in. pagesize is a scaled integer (see

NOTES

above). Alternatively, if --all is used, info on each possible combination of

NUMA

cell and page size is printed out.

allocpages [--pagesize] pagesize [--pagecount] pagecount [[--cellno] cellno] [--add] [--all]

Change the size of pages pool of pagesize on the host. If --add is specified, then pagecount pages are added into the pool. However, if --add wasn't specified, then the pagecount is taken as the new absolute size of the pool (this may be used to free some pages and size the pool down). The cellno modifier can be used to narrow the modification down to a single host

NUMA

cell. On the other end of spectrum lies --all which executes the modification on all

NUMA

cells.

cpu-baseline

FILE

[--features] [--migratable]

Compute baseline

CPU

which will be supported by all host CPUs given in <file>. The list of host CPUs is built by extracting all <cpu> elements from the <file>. Thus, the <file> can contain either a set of <cpu> elements separated by new lines or even a set of complete <capabilities> elements printed by capabilities command. If --features is specified then the resulting

XML

description will explicitly include all features that make up the

CPU,

without this option features that are part of the

CPU

model will not be listed in the

XML

description. If --migratable is specified, features that block migration will not be included in the resulting

CPU.

cpu-compare

FILE

[--error]

Compare

CPU

definition from

XML

<file> with host

CPU.

The

XML

<file> may contain either host or guest

CPU

definition. The host

CPU

definition is the <cpu> element and its contents as printed by capabilities command. The guest

CPU

definition is the <cpu> element and its contents from domain

XML

definition. For more information on guest

CPU

definition see: <libvirt.org/formatdomain.html#elementsCPU>. If --error is specified, the command will return an error when the given

CPU

is incompatible with host

CPU

and a message providing more details about the incompatibility will be printed out.

cpu-models arch

Print the list of

CPU

models known for the specified architecture.

echo [--shell] [--xml] [arg...]

Echo back each arg, separated by space. If --shell is specified, then the output will be single-quoted where needed, so that it is suitable for reuse in a shell context. If --xml is specified, then the output will be escaped for use in

XML.

DOMAIN COMMANDS

The following commands manipulate domains directly, as stated previously most commands take domain as the first parameter. The domain can be specified as a short integer, a name or a full

autostart [--disable] domain

Configure a domain to be automatically started at boot.

The option --disable disables autostarting.

console domain [devname] [--safe] [--force]

Connect the virtual serial console for the guest. The optional devname parameter refers to the device alias of an alternate console, serial or parallel device configured for the guest. If omitted, the primary console will be opened.

If the flag --safe is specified, the connection is only attempted if the driver supports safe console handling. This flag specifies that the server has to ensure exclusive access to console devices. Optionally the --force flag may be specified, requesting to disconnect any existing sessions, such as in a case of a broken connection.

create

FILE

[--console] [--paused] [--autodestroy] [--pass-fds N,M,...]

Create a domain from an

XML

<file>. An easy way to create the

XML

<file> is to use the dumpxml command to obtain the definition of a pre-existing guest. The domain will be paused if the --paused option is used and supported by the driver; otherwise it will be running. If --console is requested, attach to the console after creation. If --autodestroy is requested, then the guest will be automatically destroyed when virsh closes its connection to libvirt, or otherwise exits.

If --pass-fds is specified, the argument is a comma separated list of open file descriptors which should be pass on into the guest. The file descriptors will be re-numbered in the guest, starting from 3. This is only supported with container based virtualization.

Example

 virsh dumpxml <domain> > domain.xml
 vi domain.xml (or make changes with your other text editor)
 virsh create domain.xml

define

FILE

Define a domain from an

XML

<file>. The domain definition is registered but not started. If domain is already running, the changes will take effect on the next boot.

desc domain [[--live] [--config] | [--current]] [--title] [--edit] [--new-desc New description or title message]

Show or modify description and title of a domain. These values are user fields that allow to store arbitrary textual data to allow easy identification of domains. Title should be short, although it's not enforced. (See also metadata that works with

XML

based domain metadata.)

Flags --live or --config select whether this command works on live or persistent definitions of the domain. If both --live and --config are specified, the --config option takes precedence on getting the current description and both live configuration and config are updated while setting the description. --current is exclusive and implied if none of these was specified.

Flag --edit specifies that an editor with the contents of current description or title should be opened and the contents saved back afterwards.

Flag --title selects operation on the title field instead of description.

If neither of --edit and --new-desc are specified the note or description is displayed instead of being modified.

destroy domain [--graceful]

Immediately terminate the domain domain. This doesn't give the domain

OS

any chance to react, and it's the equivalent of ripping the power cord out on a physical machine. In most cases you will want to use the shutdown command instead. However, this does not delete any storage volumes used by the guest, and if the domain is persistent, it can be restarted later.

If domain is transient, then the metadata of any snapshots will be lost once the guest stops running, but the snapshot contents still exist, and a new domain with the same name and

UUID

can restore the snapshot metadata with snapshot-create.

If --graceful is specified, don't resort to extreme measures (e.g.

SIGKILL

) when the guest doesn't stop after a reasonable timeout; return an error instead.

domblkstat domain [block-device] [--human]

Get device block stats for a running domain. A block-device corresponds to a unique target name (<target dev='name'/>) or source file (<source file='name'/>) for one of the disk devices attached to domain (see also domblklist for listing these names). On a lxc or qemu domain, omitting the block-device yields device block stats summarily for the entire domain.

Use --human for a more human readable output.

Availability of these fields depends on hypervisor. Unsupported fields are missing from the output. Other fields may appear if communicating with a newer version of libvirtd.

Explanation of fields (fields appear in the following order):
  rd_req            - count of read operations
  rd_bytes          - count of read bytes
  wr_req            - count of write operations
  wr_bytes          - count of written bytes
  errs              - error count
  flush_operations  - count of flush operations
  rd_total_times    - total time read operations took (ns)
  wr_total_times    - total time write operations took (ns)
  flush_total_times - total time flush operations took (ns)
    <-- other fields provided by hypervisor -->

domifaddr domain [interface] [--full] [--source lease|agent]

Get a list of interfaces of a running domain along with their

IP

and

MAC

addresses, or limited output just for one interface if interface is specified. Note that interface can be driver dependent, it can be the name within guest

OS

or the name you would see in domain

XML.

Moreover, the whole command may require a guest agent to be configured for the queried domain under some drivers, notably qemu. If --full is specified, the interface name is always displayed when the interface has multiple addresses or alias, otherwise it only displays the interface name for the first address, and ``-'' for the others. The --source argument specifies what data source to use for the addresses, currently one of 'lease' to read

DHCP

leases, or 'agent' to query the guest

OS

via an agent. If unspecified, 'lease' is the default.

domifstat domain interface-device

Get network interface stats for a running domain.

domif-setlink domain interface-device state [--config]

Modify link state of the domain's virtual interface. Possible values for state are ``up'' and ``down''. If --config is specified, only the persistent configuration of the domain is modified, for compatibility purposes, --persistent is alias of --config. interface-device can be the interface's target name or the

MAC

address.

domif-getlink domain interface-device [--config]

Query link state of the domain's virtual interface. If --config is specified, query the persistent configuration, for compatibility purposes, --persistent is alias of --config.

interface-device can be the interface's target name or the

MAC

address.

domiftune domain interface-device [[--config] [--live] | [--current]] [--inbound average,peak,burst,floor] [--outbound average,peak,burst]

Set or query the domain's network interface's bandwidth parameters. interface-device can be the interface's target name (<target dev='name'/>), or the

MAC

address.

If no --inbound or --outbound is specified, this command will query and show the bandwidth settings. Otherwise, it will set the inbound or outbound bandwidth. average,peak,burst,floor is the same as in command attach-interface. Values for average, peak and floor are expressed in kilobytes per second, while burst is expressed in kilobytes in a single burst at peak speed as described in the Network

XML

documentation at <libvirt.org/formatnetwork.html#elementQoS>.

To clear inbound or outbound settings, use --inbound or --outbound respectfully with average value of zero.

If --live is specified, affect a running guest. If --config is specified, affect the next boot of a persistent guest. If --current is specified, affect the current guest state. Both --live and --config flags may be given, but --current is exclusive. If no flag is specified, behavior is different depending on hypervisor.

dommemstat domain [--period seconds] [[--config] [--live] | [--current]]

Get memory stats for a running domain.

Availability of these fields depends on hypervisor. Unsupported fields are missing from the output. Other fields may appear if communicating with a newer version of libvirtd.

Explanation of fields:
  swap_in           - The amount of data read from swap space (in kB)
  swap_out          - The amount of memory written out to swap space (in kB)
  major_fault       - The number of page faults where disk 

IO

 was required
  minor_fault       - The number of other page faults
  unused            - The amount of memory left unused by the system (in kB)
  available         - The amount of usable memory as seen by the domain (in kB)
  actual            - Current balloon value (in 

KB

)
  rss               - Resident Set Size of the running domain's process (in kB)
  usable            - The amount of memory which can be reclaimed by balloon without causing host swapping (in

KB

)
  last-update       - Timestamp of the last update of statistics (in seconds)

For

QEMU/KVM

with a memory balloon, setting the optional --period to a value larger than 0 in seconds will allow the balloon driver to return additional statistics which will be displayed by subsequent dommemstat commands. Setting the --period to 0 will stop the balloon driver collection, but does not clear the statistics in the balloon driver. Requires at least

QEMU/KVM 1.5

to be running on the host.

The --live, --config, and --current flags are only valid when using the --period option in order to set the collection period for the balloon driver. If --live is specified, only the running guest collection period is affected. If --config is specified, affect the next boot of a persistent guest. If --current is specified, affect the current guest state.

Both --live and --config flags may be given, but --current is exclusive. If no flag is specified, behavior is different depending on the guest state.

domblkerror domain

Show errors on block devices. This command usually comes handy when domstate command says that a domain was paused due to I/O error. The domblkerror command lists all block devices in error state and the error seen on each of them.

domblkinfo domain block-device [--human]

Get block device size info for a domain. A block-device corresponds to a unique target name (<target dev='name'/>) or source file (<source file='name'/>) for one of the disk devices attached to domain (see also domblklist for listing these names). If --human is set, the output will have a human readable output.

domblklist domain [--inactive] [--details]

Print a table showing the brief information of all block devices associated with domain. If --inactive is specified, query the block devices that will be used on the next boot, rather than those currently in use by a running domain. If --details is specified, disk type and device value will also be printed. Other contexts that require a block device name (such as domblkinfo or snapshot-create for disk snapshots) will accept either target or unique source names printed by this command.

domstats [--raw] [--enforce] [--backing] [--state] [--cpu-total] [--balloon] [--vcpu] [--interface] [--block] [--perf] [[--list-active] [--list-inactive] [--list-persistent] [--list-transient] [--list-running] [--list-paused] [--list-shutoff] [--list-other]] | [domain ...]

Get statistics for multiple or all domains. Without any argument this command prints all available statistics for all domains.

The list of domains to gather stats for can be either limited by listing the domains as a space separated list, or by specifying one of the filtering flags --list-*. (The approaches can't be combined.)

By default some of the returned fields may be converted to more human friendly values by a set of pretty-printers. To suppress this behavior use the --raw flag.

The individual statistics groups are selectable via specific flags. By default all supported statistics groups are returned. Supported statistics groups flags are: --state, --cpu-total, --balloon, --vcpu, --interface, --block, --perf.

Note that - depending on the hypervisor type and version or the domain state - not all of the following statistics may be returned.

When selecting the --state group the following fields are returned:

 "state.state" - state of the VM, returned as number from
                 virDomainState enum
 "state.reason" - reason for entering given state, returned
                  as int from virDomain*Reason enum corresponding
                  to given state

--cpu-total returns:

 "cpu.time" - total cpu time spent for this domain in nanoseconds
 "cpu.user" - user cpu time spent in nanoseconds
 "cpu.system" - system cpu time spent in nanoseconds

--balloon returns:

 "balloon.current" - the memory in kiB currently used
 "balloon.maximum" - the maximum memory in kiB allowed
 "balloon.swap_in" - the amount of data read from swap space (in kB)
 "balloon.swap_out" - the amount of memory written out to swap
                      space (in kB)
 "balloon.major_fault" - the number of page faults then disk IO
                         was required
 "balloon.minor_fault" - the number of other page faults
 "balloon.unused" - the amount of memory left unused by the
                    system (in kB)
 "balloon.available" - the amount of usable memory as seen by
                       the domain (in kB)
 "balloon.rss" - Resident Set Size of running domain's process
                 (in kB)
 "balloon.usable" - the amount of memory which can be reclaimed by
                    balloon without causing host swapping (in KB)
 "balloon.last-update" - timestamp of the last update of statistics
                         (in seconds)

--vcpu returns:

 "vcpu.current" - current number of online virtual CPUs
 "vcpu.maximum" - maximum number of online virtual CPUs
 "vcpu.<num>.state" - state of the virtual CPU <num>, as
                      number from virVcpuState enum
 "vcpu.<num>.time" - virtual cpu time spent by virtual
                     CPU <num> (in microseconds)
 "vcpu.<num>.wait" - virtual cpu time spent by virtual
                     CPU <num> waiting on I/O (in microseconds)
 "vcpu.<num>.halted" - virtual CPU <num> is halted: yes or
                       no (may indicate the processor is idle
                       or even disabled, depending on the
                       architecture)

--interface returns:

 "net.count" - number of network interfaces on this domain
 "net.<num>.name" - name of the interface <num>
 "net.<num>.rx.bytes" - number of bytes received
 "net.<num>.rx.pkts" - number of packets received
 "net.<num>.rx.errs" - number of receive errors
 "net.<num>.rx.drop" - number of receive packets dropped
 "net.<num>.tx.bytes" - number of bytes transmitted
 "net.<num>.tx.pkts" - number of packets transmitted
 "net.<num>.tx.errs" - number of transmission errors
 "net.<num>.tx.drop" - number of transmit packets dropped

--perf returns the statistics of all enabled perf events:

 "perf.cmt" - the cache usage in Byte currently used
 "perf.mbmt" - total system bandwidth from one level of cache
 "perf.mbml" - bandwidth of memory traffic for a memory controller
 "perf.cpu_cycles" - the count of cpu cycles (total/elapsed)
 "perf.instructions" - the count of instructions
 "perf.cache_references" - the count of cache hits
 "perf.cache_misses" - the count of caches misses
 "perf.branch_instructions" - the count of branch instructions
 "perf.branch_misses" - the count of branch misses
 "perf.bus_cycles" - the count of bus cycles
 "perf.stalled_cycles_frontend" - the count of stalled frontend
                                  cpu cycles
 "perf.stalled_cycles_backend" - the count of stalled backend
                                 cpu cycles
 "perf.ref_cpu_cycles" - the count of ref cpu cycles
 "perf.cpu_clock" - the count of cpu clock time
 "perf.task_clock" - the count of task clock time
 "perf.page_faults" - the count of page faults
 "perf.context_switches" - the count of context switches
 "perf.cpu_migrations" - the count of cpu migrations
 "perf.page_faults_min" - the count of minor page faults
 "perf.page_faults_maj" - the count of major page faults
 "perf.alignment_faults" - the count of alignment faults
 "perf.emulation_faults" - the count of emulation faults

See the perf command for more details about each event.

--block returns information about disks associated with each domain. Using the --backing flag extends this information to cover all resources in the backing chain, rather than the default of limiting information to the active layer for each guest disk. Information listed includes:

 "block.count" - number of block devices being listed
 "block.<num>.name" - name of the target of the block
                      device <num> (the same name for
                      multiple entries if I<--backing>
                      is present)
 "block.<num>.backingIndex" - when I<--backing> is present,
                              matches up with the <backingStore>
                              index listed in domain XML for
                              backing files
 "block.<num>.path" - file source of block device <num>, if
                      it is a local file or block device
 "block.<num>.rd.reqs" - number of read requests
 "block.<num>.rd.bytes" - number of read bytes
 "block.<num>.rd.times" - total time (ns) spent on reads
 "block.<num>.wr.reqs" - number of write requests
 "block.<num>.wr.bytes" - number of written bytes
 "block.<num>.wr.times" - total time (ns) spent on writes
 "block.<num>.fl.reqs" - total flush requests
 "block.<num>.fl.times" - total time (ns) spent on cache flushing
 "block.<num>.errors" - Xen only: the 'oo_req' value
 "block.<num>.allocation" - offset of highest written sector in bytes
 "block.<num>.capacity" - logical size of source file in bytes
 "block.<num>.physical" - physical size of source file in bytes
 "block.<num>.threshold" - threshold (in bytes) for delivering the
                           VIR_DOMAIN_EVENT_ID_BLOCK_THRESHOLD event
                           See domblkthreshold.

Selecting a specific statistics groups doesn't guarantee that the daemon supports the selected group of stats. Flag --enforce forces the command to fail if the daemon doesn't support the selected group.

domiflist domain [--inactive]

Print a table showing the brief information of all virtual interfaces associated with domain. If --inactive is specified, query the virtual interfaces that will be used on the next boot, rather than those currently in use by a running domain. Other contexts that require a

MAC

address of virtual interface (such as detach-interface or domif-setlink) will accept the

MAC

address printed by this command.

blockcommit domain path [bandwidth] [--bytes] [base] [--shallow] [top] [--delete] [--keep-relative] [--wait [--async] [--verbose]] [--timeout seconds] [--active] [{--pivot | --keep-overlay}]

Reduce the length of a backing image chain, by committing changes at the top of the chain (snapshot or delta files) into backing images. By default, this command attempts to flatten the entire chain. If base and/or top are specified as files within the backing chain, then the operation is constrained to committing just that portion of the chain; --shallow can be used instead of base to specify the immediate backing file of the resulting top image to be committed. The files being committed are rendered invalid, possibly as soon as the operation starts; using the --delete flag will attempt to remove these invalidated files at the successful completion of the commit operation. When the --keep-relative flag is used, the backing file paths will be kept relative.

When top is omitted or specified as the active image, it is also possible to specify --active to trigger a two-phase active commit. In the first phase, top is copied into base and the job can only be canceled, with top still containing data not yet in base. In the second phase, top and base remain identical until a call to blockjob with the --abort flag (keeping top as the active image that tracks changes from that point in time) or the --pivot flag (making base the new active image and invalidating top).

By default, this command returns as soon as possible, and data for the entire disk is committed in the background; the progress of the operation can be checked with blockjob. However, if --wait is specified, then this command will block until the operation completes (or for --active, enters the second phase), or until the operation is canceled because the optional timeout in seconds elapses or

SIGINT

is sent (usually with "Ctrl-C"). Using --verbose along with --wait will produce periodic status updates. If job cancellation is triggered, --async will return control to the user as fast as possible, otherwise the command may continue to block a little while longer until the job is done cleaning up. Using --pivot is shorthand for combining --active --wait with an automatic blockjob --pivot; and using --keep-overlay is shorthand for combining --active --wait with an automatic blockjob --abort.

path specifies fully-qualified path of the disk; it corresponds to a unique target name (<target dev='name'/>) or source file (<source file='name'/>) for one of the disk devices attached to domain (see also domblklist for listing these names). bandwidth specifies copying bandwidth limit in MiB/s, although for qemu, it may be non-zero only for an online domain. For further information on the bandwidth argument see the corresponding section for the blockjob command.

blockcopy domain path { dest [format] [--blockdev] | --xml file } [--shallow] [--reuse-external] [bandwidth] [--wait [--async] [--verbose]] [{--pivot | --finish}] [--timeout seconds] [granularity] [buf-size] [--bytes] [--transient-job]

Copy a disk backing image chain to a destination. Either dest as the destination file name, or --xml with the name of an

XML

file containing a top-level <disk> element describing the destination, must be present. Additionally, if dest is given, format should be specified to declare the format of the destination (if format is omitted, then libvirt will reuse the format of the source, or with --reuse-external will be forced to probe the destination format, which could be a potential security hole). The command supports --raw as a boolean flag synonym for --format=raw. When using dest, the destination is treated as a regular file unless --blockdev is used to signal that it is a block device. By default, this command flattens the entire chain; but if --shallow is specified, the copy shares the backing chain.

If --reuse-external is specified, then the destination must exist and have sufficient space to hold the copy. If --shallow is used in conjunction with --reuse-external then the pre-created image must have guest visible contents identical to guest visible contents of the backing file of the original image. This may be used to modify the backing file names on the destination.

By default, the copy job runs in the background, and consists of two phases. Initially, the job must copy all data from the source, and during this phase, the job can only be canceled to revert back to the source disk, with no guarantees about the destination. After this phase completes, both the source and the destination remain mirrored until a call to blockjob with the --abort and --pivot flags pivots over to the copy, or a call without --pivot leaves the destination as a faithful copy of that point in time. However, if --wait is specified, then this command will block until the mirroring phase begins, or cancel the operation if the optional timeout in seconds elapses or

SIGINT

is sent (usually with "Ctrl-C"). Using --verbose along with --wait will produce periodic status updates. Using --pivot (similar to blockjob --pivot) or --finish (similar to blockjob --abort) implies --wait, and will additionally end the job cleanly rather than leaving things in the mirroring phase. If job cancellation is triggered by timeout or by --finish, --async will return control to the user as fast as possible, otherwise the command may continue to block a little while longer until the job has actually cancelled.

path specifies fully-qualified path of the disk. bandwidth specifies copying bandwidth limit in MiB/s. Specifying a negative value is interpreted as an unsigned long long value that might be essentially unlimited, but more likely would overflow; it is safer to use 0 for that purpose. For further information on the bandwidth argument see the corresponding section for the blockjob command. Specifying granularity allows fine-tuning of the granularity that will be copied when a dirty region is detected; larger values trigger less I/O overhead but may end up copying more data overall (the default value is usually correct); hypervisors may restrict this to be a power of two or fall within a certain range. Specifying buf-size will control how much data can be simultaneously in-flight during the copy; larger values use more memory but may allow faster completion (the default value is usually correct).

--transient-job allows to specify that the user does not require the job to be recovered if the

VM

crashes or is turned off before the job completes. This flag removes the restriction of copy jobs to transient domains if that restriction is applied by the hypervisor.

blockpull domain path [bandwidth] [--bytes] [base] [--wait [--verbose] [--timeout seconds] [--async]] [--keep-relative]

Populate a disk from its backing image chain. By default, this command flattens the entire chain; but if base is specified, containing the name of one of the backing files in the chain, then that file becomes the new backing file and only the intermediate portion of the chain is pulled. Once all requested data from the backing image chain has been pulled, the disk no longer depends on that portion of the backing chain.

By default, this command returns as soon as possible, and data for the entire disk is pulled in the background; the progress of the operation can be checked with blockjob. However, if --wait is specified, then this command will block until the operation completes, or cancel the operation if the optional timeout in seconds elapses or

SIGINT

is sent (usually with "Ctrl-C"). Using --verbose along with --wait will produce periodic status updates. If job cancellation is triggered, --async will return control to the user as fast as possible, otherwise the command may continue to block a little while longer until the job is done cleaning up.

Using the --keep-relative flag will keep the backing chain names relative.

path specifies fully-qualified path of the disk; it corresponds to a unique target name (<target dev='name'/>) or source file (<source file='name'/>) for one of the disk devices attached to domain (see also domblklist for listing these names). bandwidth specifies copying bandwidth limit in MiB/s. For further information on the bandwidth argument see the corresponding section for the blockjob command.

blkdeviotune domain device [[--config] [--live] | [--current]] [[total-bytes-sec] | [read-bytes-sec] [write-bytes-sec]] [[total-iops-sec] | [read-iops-sec] [write-iops-sec]] [[total-bytes-sec-max] | [read-bytes-sec-max] [write-bytes-sec-max]] [[total-iops-sec-max] | [read-iops-sec-max] [write-iops-sec-max]] [[total-bytes-sec-max-length] | [read-bytes-sec-max-length] [write-bytes-sec-max-length]] [[total-iops-sec-max-length] | [read-iops-sec-max-length] [write-iops-sec-max-length]] [size-iops-sec] [group-name]

Set or query the block disk io parameters for a block device of domain. device specifies a unique target name (<target dev='name'/>) or source file (<source file='name'/>) for one of the disk devices attached to domain (see also domblklist for listing these names).

If no limit is specified, it will query current I/O limits setting. Otherwise, alter the limits with these flags: --total-bytes-sec specifies total throughput limit as a scaled integer, the default being bytes per second if no suffix is specified. --read-bytes-sec specifies read throughput limit as a scaled integer, the default being bytes per second if no suffix is specified. --write-bytes-sec specifies write throughput limit as a scaled integer, the default being bytes per second if no suffix is specified. --total-iops-sec specifies total I/O operations limit per second. --read-iops-sec specifies read I/O operations limit per second. --write-iops-sec specifies write I/O operations limit per second. --total-bytes-sec-max specifies maximum total throughput limit as a scaled integer, the default being bytes per second if no suffix is specified --read-bytes-sec-max specifies maximum read throughput limit as a scaled integer, the default being bytes per second if no suffix is specified. --write-bytes-sec-max specifies maximum write throughput limit as a scaled integer, the default being bytes per second if no suffix is specified. --total-iops-sec-max specifies maximum total I/O operations limit per second. --read-iops-sec-max specifies maximum read I/O operations limit per second. --write-iops-sec-max specifies maximum write I/O operations limit per second. --total-bytes-sec-max-length specifies duration in seconds to allow maximum total throughput limit. --read-bytes-sec-max-length specifies duration in seconds to allow maximum read throughput limit. --write-bytes-sec-max-length specifies duration in seconds to allow maximum write throughput limit. --total-iops-sec-max-length specifies duration in seconds to allow maximum total I/O operations limit. --read-iops-sec-max-length specifies duration in seconds to allow maximum read I/O operations limit. --write-iops-sec-max-length specifies duration in seconds to allow maximum write I/O operations limit. --size-iops-sec specifies size I/O operations limit per second. --group-name specifies group name to share I/O quota between multiple drives. For a qemu domain, if no name is provided, then the default is to have a single group for each device.

Older versions of virsh only accepted these options with underscore instead of dash, as in --total_bytes_sec.

Bytes and iops values are independent, but setting only one value (such as --read-bytes-sec) resets the other two in that category to unlimited. An explicit 0 also clears any limit. A non-zero value for a given total cannot be mixed with non-zero values for read or write.

It is up to the hypervisor to determine how to handle the length values. For the qemu hypervisor, if an I/O limit value or maximum value is set, then the default value of 1 second will be displayed. Supplying a 0 will reset the value back to the default.

If --live is specified, affect a running guest. If --config is specified, affect the next boot of a persistent guest. If --current is specified, affect the current guest state. When setting the disk io parameters both --live and --config flags may be given, but --current is exclusive. For querying only one of --live, --config or --current can be specified. If no flag is specified, behavior is different depending on hypervisor.

blockjob domain path { [--abort] [--async] [--pivot] | [--info] [--raw] [--bytes] | [bandwidth] }

Manage active block operations. There are three mutually-exclusive modes: --info, bandwidth, and --abort. --async and --pivot imply abort mode; --raw implies info mode; and if no mode was given, --info mode is assumed.

path specifies fully-qualified path of the disk; it corresponds to a unique target name (<target dev='name'/>) or source file (<source file='name'/>) for one of the disk devices attached to domain (see also domblklist for listing these names).

In --abort mode, the active job on the specified disk will be aborted. If --async is also specified, this command will return immediately, rather than waiting for the cancellation to complete. If --pivot is specified, this requests that an active copy or active commit job be pivoted over to the new image.

In --info mode, the active job information on the specified disk will be printed. By default, the output is a single human-readable summary line; this format may change in future versions. Adding --raw lists each field of the struct, in a stable format. If the --bytes flag is set, then the command errors out if the server could not supply bytes/s resolution; when omitting the flag, raw output is listed in MiB/s and human-readable output automatically selects the best resolution supported by the server.

bandwidth can be used to set bandwidth limit for the active job in MiB/s. If --bytes is specified then the bandwidth value is interpreted in bytes/s. Specifying a negative value is interpreted as an unsigned long value or essentially unlimited. The hypervisor can choose whether to reject the value or convert it to the maximum value allowed. Optionally a scaled positive number may be used as bandwidth (see

NOTES

above). Using --bytes with a scaled value allows to use finer granularity. A scaled value used without --bytes will be rounded down to MiB/s. Note that the --bytes may be unsupported by the hypervisor.

domblkthreshold domain dev threshold

Set the threshold value for delivering the block-threshold event. dev specifies the disk device target or backing chain element of given device using the 'target[1]' syntax. threshold is a scaled value of the offset. If the block device should write beyond that offset the event will be delivered.

blockresize domain path size

Resize a block device of domain while the domain is running, path specifies the absolute path of the block device; it corresponds to a unique target name (<target dev='name'/>) or source file (<source file='name'/>) for one of the disk devices attached to domain (see also domblklist for listing these names).

size is a scaled integer (see

NOTES

above) which defaults to KiB (blocks of 1024 bytes) if there is no suffix. You must use a suffix of ``B'' to get bytes (note that for historical reasons, this differs from vol-resize which defaults to bytes without a suffix).

domdisplay domain [--include-password] [[--type] type] [--all]

Output a

URI

which can be used to connect to the graphical display of the domain via

VNC, SPICE

or

RDP.

The particular graphical display type can be selected using the type parameter (e.g. ``vnc'', ``spice'', ``rdp''). If --include-password is specified, the

SPICE

channel password will be included in the

URI.

If --all is specified, then all show all possible graphical displays, for a

VM

could have more than one graphical displays.

domfsinfo domain

Show a list of mounted filesystems within the running domain. The list contains mountpoints, names of a mounted device in the guest, filesystem types, and unique target names used in the domain

XML

(<target dev='name'/>).

Note that this command requires a guest agent configured and running in the domain's guest

OS.

domfsfreeze domain [[--mountpoint] mountpoint...]

Freeze mounted filesystems within a running domain to prepare for consistent snapshots.

The --mountpoint option takes a parameter mountpoint, which is a mount point path of the filesystem to be frozen. This option can occur multiple times. If this is not specified, every mounted filesystem is frozen.

Note: snapshot-create command has a --quiesce option to freeze and thaw the filesystems automatically to keep snapshots consistent. domfsfreeze command is only needed when a user wants to utilize the native snapshot features of storage devices not supported by libvirt.

domfsthaw domain [[--mountpoint] mountpoint...]

Thaw mounted filesystems within a running domain, which have been frozen by domfsfreeze command.

The --mountpoint option takes a parameter mountpoint, which is a mount point path of the filesystem to be thawed. This option can occur multiple times. If this is not specified, every mounted filesystem is thawed.

domfstrim domain [--minimum bytes] [--mountpoint mountPoint]

Issue a fstrim command on all mounted filesystems within a running domain. It discards blocks which are not in use by the filesystem. If --minimum bytes is specified, it tells guest kernel length of contiguous free range. Smaller than this may be ignored (this is a hint and the guest may not respect it). By increasing this value, the fstrim operation will complete more quickly for filesystems with badly fragmented free space, although not all blocks will be discarded. The default value is zero, meaning ``discard every free block''. Moreover, if a user wants to trim only one mount point, it can be specified via optional --mountpoint parameter.

domhostname domain

Returns the hostname of a domain, if the hypervisor makes it available.

dominfo domain

Returns basic information about the domain.

domuuid domain-name-or-id

Convert a domain name or id to domain

UUID

domid domain-name-or-uuid

Convert a domain name (or

UUID

) to a domain id

domjobabort domain

Abort the currently running domain job.

domjobinfo domain [--completed]

Returns information about jobs running on a domain. --completed tells virsh to return information about a recently finished job. Statistics of a completed job are automatically destroyed once read or when libvirtd is restarted. Note that time information returned for completed migrations may be completely irrelevant unless both source and destination hosts have synchronized time (i.e.,

NTP

daemon is running on both of them).

domname domain-id-or-uuid

Convert a domain Id (or

UUID

) to domain name

domrename domain new-name

Rename a domain. This command changes current domain name to the new name specified in the second argument.

Note: Domain must be inactive and without snapshots.

domstate domain [--reason]

Returns state about a domain. --reason tells virsh to also print reason for the state.

domcontrol domain

Returns state of an interface to

VMM

used to control a domain. For states other than ``ok'' or ``error'' the command also prints number of seconds elapsed since the control interface entered its current state.

domtime domain { [--now] [--pretty] [--sync] [--time time] }

Gets or sets the domain's system time. When run without any arguments (but domain), the current domain's system time is printed out. The --pretty modifier can be used to print the time in more human readable form.

When --time time is specified, the domain's time is not gotten but set instead. The --now modifier acts like if it was an alias for --time $now, which means it sets the time that is currently on the host virsh is running at. In both cases (setting and getting), time is in seconds relative to Epoch of 1970-01-01 in

UTC.

The --sync modifies the set behavior a bit: The time passed is ignored, but the time to set is read from domain's

RTC

instead. Please note, that some hypervisors may require a guest agent to be configured in order to get or set the guest time.

domxml-from-native format config

Convert the file config in the native guest configuration format named by format to a domain

XML

format. For

QEMU/KVM

hypervisor, the format argument must be qemu-argv. For Xen hypervisor, the format argument may be xen-xm, xen-xl, or xen-sxpr. For

LXC

hypervisor, the format argument must be lxc-tools.

domxml-to-native format { [--xml] xml | --domain domain-name-or-id-or-uuid }

Convert the file xml into domain

XML

format or convert an existing --domain to the native guest configuration format named by format. The xml and --domain arguments are mutually exclusive.

For the

QEMU/KVM

hypervisor, the format argument must be qemu-argv.

For the Xen hypervisor, the format argument may be xen-xm, xen-xl, or xen-sxpr.

For the

LXC

hypervisor, the format argument must be lxc-tools.

dump domain corefilepath [--bypass-cache] { [--live] | [--crash] | [--reset] } [--verbose] [--memory-only] [--format string]

Dumps the core of a domain to a file for analysis. If --live is specified, the domain continues to run until the core dump is complete, rather than pausing up front. If --crash is specified, the domain is halted with a crashed status, rather than merely left in a paused state. If --reset is specified, the domain is reset after successful dump. Note, these three switches are mutually exclusive. If --bypass-cache is specified, the save will avoid the file system cache, although this may slow down the operation. If --memory-only is specified, the file is elf file, and will only include domain's memory and cpu common register value. It is very useful if the domain uses host devices directly. --format string is used to specify the format of 'memory-only' dump, and string can be one of them: elf, kdump-zlib(kdump-compressed format with zlib-compressed), kdump-lzo(kdump-compressed format with lzo-compressed), kdump-snappy(kdump-compressed format with snappy-compressed).

The progress may be monitored using domjobinfo virsh command and canceled with domjobabort command (sent by another virsh instance). Another option is to send

SIGINT

(usually with "Ctrl-C") to the virsh process running dump command. --verbose displays the progress of dump.

NOTE:

Some hypervisors may require the user to manually ensure proper permissions on file and path specified by argument corefilepath.

NOTE:

Crash dump in a old kvmdump format is being obsolete and cannot be loaded and processed by crash utility since its version 6.1.0. A --memory-only option is required in order to produce valid

ELF

file which can be later processed by the crash utility.

dumpxml domain [--inactive] [--security-info] [--update-cpu] [--migratable]

Output the domain information as an

XML

dump to stdout, this format can be used by the create command. Additional options affecting the

XML

dump may be used. --inactive tells virsh to dump domain configuration that will be used on next start of the domain as opposed to the current domain configuration. Using --security-info will also include security sensitive information in the

XML

dump. --update-cpu updates domain

CPU

requirements according to host

CPU.

With --migratable one can request an

XML

that is suitable for migrations, i.e., compatible with older libvirt releases and possibly amended with internal run-time options. This option may automatically enable other options (--update-cpu, --security-info, ...) as necessary.

edit domain

Edit the

XML

configuration file for a domain, which will affect the next boot of the guest.

This is equivalent to:

 virsh dumpxml --inactive --security-info domain > domain.xml
 vi domain.xml (or make changes with your other text editor)
 virsh define domain.xml

except that it does some error checking.

The editor used can be supplied by the $VISUAL or $EDITOR environment variables, and defaults to "vi".

event {[domain] { event | --all } [--loop] [--timeout seconds] [--timestamp] | --list}

Wait for a class of domain events to occur, and print appropriate details of events as they happen. The events can optionally be filtered by domain. Using --list as the only argument will provide a list of possible event values known by this client, although the connection might not allow registering for all these events. It is also possible to use --all instead of event to register for all possible event types at once.

By default, this command is one-shot, and returns success once an event occurs; you can send

SIGINT

(usually via "Ctrl-C") to quit immediately. If --timeout is specified, the command gives up waiting for events after seconds have elapsed. With --loop, the command prints all events until a timeout or interrupt key.

When --timestamp is used, a human-readable timestamp will be printed before the event.

iothreadinfo domain [[--live] [--config] | [--current]]

Display basic domain IOThreads information including the IOThread

ID

and the

CPU

Affinity for each IOThread.

If --live is specified, get the IOThreads data from the running guest. If the guest is not running, an error is returned. If --config is specified, get the IOThreads data from the next boot of a persistent guest. If --current is specified or --live and --config are not specified, then get the IOThread data based on the current guest state.

iothreadpin domain iothread cpulist [[--live] [--config] | [--current]]

Change the pinning of a domain IOThread to host physical CPUs. In order to retrieve a list of all IOThreads, use iothreadinfo. To pin an iothread specify the cpulist desired for the IOThread

ID

as listed in the iothreadinfo output.

cpulist is a list of physical

CPU

numbers. Its syntax is a comma separated list and a special markup using '-' and '^' (ex. '0-4', '0-3,^2') can also be allowed. The '-' denotes the range and the '^' denotes exclusive. If you want to reset iothreadpin setting, that is, to pin an iothread to all physical cpus, simply specify 'r' as a cpulist.

If --live is specified, affect a running guest. If the guest is not running, an error is returned. If --config is specified, affect the next boot of a persistent guest. If --current is specified or --live and --config are not specified, affect the current guest state. Both --live and --config flags may be given if cpulist is present, but --current is exclusive. If no flag is specified, behavior is different depending on hypervisor.

Note: The expression is sequentially evaluated, so ``0-15,^8'' is identical to ``9-14,0-7,15'' but not identical to ``^8,0-15''.

iothreadadd domain iothread_id [[--config] [--live] | [--current]]

Add a new IOThread to the domain using the specified iothread_id. If the iothread_id already exists, the command will fail. The iothread_id must be greater than zero.

If --live is specified, affect a running guest. If the guest is not running an error is returned. If --config is specified, affect the next boot of a persistent guest. If --current is specified or --live and --config are not specified, affect the current guest state.

iothreaddel domain iothread_id [[--config] [--live] | [--current]]

Delete an IOThread from the domain using the specified iothread_id. If an IOThread is currently assigned to a disk resource such as via the attach-disk command, then the attempt to remove the IOThread will fail. If the iothread_id does not exist an error will occur.

If --live is specified, affect a running guest. If the guest is not running an error is returned. If --config is specified, affect the next boot of a persistent guest. If --current is specified or --live and --config are not specified, affect the current guest state.

managedsave domain [--bypass-cache] [{--running | --paused}] [--verbose]

Save and destroy (stop) a running domain, so it can be restarted from the same state at a later time. When the virsh start command is next run for the domain, it will automatically be started from this saved state. If --bypass-cache is specified, the save will avoid the file system cache, although this may slow down the operation.

The progress may be monitored using domjobinfo virsh command and canceled with domjobabort command (sent by another virsh instance). Another option is to send

SIGINT

(usually with "Ctrl-C") to the virsh process running managedsave command. --verbose displays the progress of save.

Normally, starting a managed save will decide between running or paused based on the state the domain was in when the save was done; passing either the --running or --paused flag will allow overriding which state the start should use.

The dominfo command can be used to query whether a domain currently has any managed save image.

managedsave-remove domain

Remove the managedsave state file for a domain, if it exists. This ensures the domain will do a full boot the next time it is started.

maxvcpus [type]

Provide the maximum number of virtual CPUs supported for a guest

VM

on this connection. If provided, the type parameter must be a valid type attribute for the <domain> element of

XML.

cpu-stats domain [--total] [start] [count]

Provide cpu statistics information of a domain. The domain should be running. Default it shows stats for all CPUs, and a total. Use --total for only the total stats, start for only the per-cpu stats of the CPUs from start, count for only count CPUs' stats.

metadata domain [[--live] [--config] | [--current]] [--edit] [uri] [key] [set] [--remove]

Show or modify custom

XML

metadata of a domain. The metadata is a user defined

XML

that allows to store arbitrary

XML

data in the domain definition. Multiple separate custom metadata pieces can be stored in the domain

XML.

The pieces are identified by a private

XML

namespace provided via the uri argument. (See also desc that works with textual metadata of a domain.)

Flags --live or --config select whether this command works on live or persistent definitions of the domain. If both --live and --config are specified, the --config option takes precedence on getting the current description and both live configuration and config are updated while setting the description. --current is exclusive and implied if none of these was specified.

Flag --remove specifies that the metadata element specified by the uri argument should be removed rather than updated.

Flag --edit specifies that an editor with the metadata identified by the uri argument should be opened and the contents saved back afterwards. Otherwise the new contents can be provided via the set argument.

When setting metadata via --edit or set the key argument must be specified and is used to prefix the custom elements to bind them to the private namespace.

If neither of --edit and set are specified the

XML

metadata corresponding to the uri namespace is displayed instead of being modified.

migrate [--live] [--offline] [--direct] [--p2p [--tunnelled]] [--persistent] [--undefinesource] [--suspend] [--copy-storage-all] [--copy-storage-inc] [--change-protection] [--unsafe] [--verbose] [--rdma-pin-all] [--abort-on-error] [--postcopy] [--postcopy-after-precopy] domain desturi [migrateuri] [graphicsuri] [listen-address] [dname] [--timeout seconds [--timeout-suspend | --timeout-postcopy]] [--xml file] [--migrate-disks disk-list] [--disks-port port] [--compressed] [--comp-methods method-list] [--comp-mt-level] [--comp-mt-threads] [--comp-mt-dthreads] [--comp-xbzrle-cache] [--auto-converge] [auto-converge-initial] [auto-converge-increment] [--persistent-xml file] [--tls]

Migrate domain to another host. Add --live for live migration; <--p2p> for peer-2-peer migration; --direct for direct migration; or --tunnelled for tunnelled migration. --offline migrates domain definition without starting the domain on destination and without stopping it on source host. Offline migration may be used with inactive domains and it must be used with --persistent option. --persistent leaves the domain persistent on destination host, --undefinesource undefines the domain on the source host, and --suspend leaves the domain paused on the destination host. --copy-storage-all indicates migration with non-shared storage with full disk copy, --copy-storage-inc indicates migration with non-shared storage with incremental copy (same base image shared between source and destination). In both cases the disk images have to exist on destination host, the --copy-storage-... options only tell libvirt to transfer data from the images on source host to the images found at the same place on the destination host. By default only non-shared non-readonly images are transferred. Use --migrate-disks to explicitly specify a list of disk targets to transfer via the comma separated disk-list argument. --change-protection enforces that no incompatible configuration changes will be made to the domain while the migration is underway; this flag is implicitly enabled when supported by the hypervisor, but can be explicitly used to reject the migration if the hypervisor lacks change protection support. --verbose displays the progress of migration. --abort-on-error cancels the migration if a soft error (for example I/O error) happens during the migration. --postcopy enables post-copy logic in migration, but does not actually start post-copy, i.e., migration is started in pre-copy mode. Once migration is running, the user may switch to post-copy using the migrate-postcopy command sent from another virsh instance or use --postcopy-after-precopy along with --postcopy to let libvirt automatically switch to post-copy after the first pass of pre-copy is finished.

--auto-converge forces convergence during live migration. The initial guest

CPU

throttling rate can be set with auto-converge-initial. If the initial throttling rate is not enough to ensure convergence, the rate is periodically increased by auto-converge-increment.

--rdma-pin-all can be used with

RDMA

migration (i.e., when migrateuri starts with rdma://) to tell the hypervisor to pin all domain's memory at once before migration starts rather than letting it pin memory pages as needed.

Note: Individual hypervisors usually do not support all possible types of migration. For example,

QEMU

does not support direct migration.

In some cases libvirt may refuse to migrate the domain because doing so may lead to potential problems such as data corruption, and thus the migration is considered unsafe. For

QEMU

domain, this may happen if the domain uses disks without explicitly setting cache mode to ``none''. Migrating such domains is unsafe unless the disk images are stored on coherent clustered filesystem, such as

GFS2

or

GPFS.

If you are sure the migration is safe or you just do not care, use --unsafe to force the migration.

dname is used for renaming the domain to new name during migration, which also usually can be omitted. Likewise, --xml file is usually omitted, but can be used to supply an alternative

XML

file for use on the destination to supply a larger set of changes to any host-specific portions of the domain

XML,

such as accounting for naming differences between source and destination in accessing underlying storage. If --persistent is enabled, --persistent-xml file can be used to supply an alternative

XML

file which will be used as the persistent domain definition on the destination host.

--timeout seconds tells virsh to run a specified action when live migration exceeds that many seconds. It can only be used with --live. If --timeout-suspend is specified, the domain will be suspended after the timeout and the migration will complete offline; this is the default if no --timeout-* option is specified on the command line. When --timeout-postcopy is used, virsh will switch migration from pre-copy to post-copy upon timeout; migration has to be started with --postcopy option for this to work.

--compressed activates compression, the compression method is chosen with --comp-methods. Supported methods are ``mt'' and ``xbzrle'' and can be used in any combination. When no methods are specified, a hypervisor default methods will be used.

QEMU

defaults to ``xbzrle''. Compression methods can be tuned further. --comp-mt-level sets compression level. Values are in range from 0 to 9, where 1 is maximum speed and 9 is maximum compression. --comp-mt-threads and --comp-mt-dthreads set the number of compress threads on source and the number of decompress threads on target respectively. --comp-xbzrle-cache sets size of page cache in bytes.

Providing --tls causes the migration to use the host configured

TLS

setup (see migrate_tls_x509_cert_dir in /etc/libvirt/qemu.conf) in order to perform the migration of the domain. Usage requires proper

TLS

setup for both source and target.

Running migration can be canceled by interrupting virsh (usually using "Ctrl-C") or by domjobabort command sent from another virsh instance.

The desturi and migrateuri parameters can be used to control which destination the migration uses. desturi is important for managed migration, but unused for direct migration; migrateuri is required for direct migration, but can usually be automatically determined for managed migration.

Note: The desturi parameter for normal migration and peer2peer migration has different semantics:

*

normal migration: the desturi is an address of the target host as seen from the client machine.

*

peer2peer migration: the desturi is an address of the target host as seen from the source machine.

When migrateuri is not specified, libvirt will automatically determine the hypervisor specific

URI.

Some hypervisors, including

QEMU,

have an optional ``migration_host'' configuration parameter (useful when the host has multiple network interfaces). If this is unspecified, libvirt determines a name by looking up the target host's configured hostname.

There are a few scenarios where specifying migrateuri may help:

*

The configured hostname is incorrect, or

DNS

is broken. If a host has a hostname which will not resolve to match one of its public

IP

addresses, then libvirt will generate an incorrect

URI.

In this case migrateuri should be explicitly specified, using an

IP

address, or a correct hostname.

*

The host has multiple network interfaces. If a host has multiple network interfaces, it might be desirable for the migration data stream to be sent over a specific interface for either security or performance reasons. In this case migrateuri should be explicitly specified, using an

IP

address associated with the network to be used.

*

The firewall restricts what ports are available. When libvirt generates a migration

URI,

it will pick a port number using hypervisor specific rules. Some hypervisors only require a single port to be open in the firewalls, while others require a whole range of port numbers. In the latter case migrateuri might be specified to choose a specific port number outside the default range in order to comply with local firewall policies.

See <libvirt.org/migration.html#uris> for more details on migration URIs.

Optional graphicsuri overrides connection parameters used for automatically reconnecting a graphical clients at the end of migration. If omitted, libvirt will compute the parameters based on target host

IP

address. In case the client does not have a direct access to the network virtualization hosts are connected to and needs to connect through a proxy, graphicsuri may be used to specify the address the client should connect to. The

URI

is formed as follows:

    protocol://hostname[:port]/[?parameters]

where protocol is either ``spice'' or ``vnc'' and parameters is a list of protocol specific parameters separated by '&'. Currently recognized parameters are ``tlsPort'' and ``tlsSubject''. For example,

    spice://target.host.com:1234/?tlsPort=4567

Optional listen-address sets the listen address that hypervisor on the destination side should bind to for incoming migration. Both IPv4 and IPv6 addresses are accepted as well as hostnames (the resolving is done on destination). Some hypervisors do not support this feature and will return an error if this parameter is used.

Optional disks-port sets the port that hypervisor on destination side should bind to for incoming disks traffic. Currently it is supported only by qemu.

migrate-setmaxdowntime domain downtime

Set maximum tolerable downtime for a domain which is being live-migrated to another host. The downtime is a number of milliseconds the guest is allowed to be down at the end of live migration.

migrate-compcache domain [--size bytes]

Sets and/or gets size of the cache (in bytes) used for compressing repeatedly transferred memory pages during live migration. When called without size, the command just prints current size of the compression cache. When size is specified, the hypervisor is asked to change compression cache to size bytes and then the current size is printed (the result may differ from the requested size due to rounding done by the hypervisor). The size option is supposed to be used while the domain is being live-migrated as a reaction to migration progress and increasing number of compression cache misses obtained from domjobinfo.

migrate-setspeed domain bandwidth

Set the maximum migration bandwidth (in MiB/s) for a domain which is being migrated to another host. bandwidth is interpreted as an unsigned long long value. Specifying a negative value results in an essentially unlimited value being provided to the hypervisor. The hypervisor can choose whether to reject the value or convert it to the maximum value allowed.

migrate-getspeed domain

Get the maximum migration bandwidth (in MiB/s) for a domain.

migrate-postcopy domain

Switch the current migration from pre-copy to post-copy. This is only supported for a migration started with --postcopy option.

numatune domain [--mode mode] [--nodeset nodeset] [[--config] [--live] | [--current]]

Set or get a domain's numa parameters, corresponding to the <numatune> element of domain

XML.

Without flags, the current settings are displayed.

mode can be one of `strict', `interleave' and `preferred' or any valid number from the virDomainNumatuneMemMode enum in case the daemon supports it. For a running domain, the mode can't be changed, and the nodeset can be changed only if the domain was started with a mode of `strict'.

nodeset is a list of numa nodes used by the host for running the domain. Its syntax is a comma separated list, with '-' for ranges and '^' for excluding a node.

If --live is specified, set scheduler information of a running guest. If --config is specified, affect the next boot of a persistent guest. If --current is specified, affect the current guest state.

reboot domain [--mode MODE-LIST]

Reboot a domain. This acts just as if the domain had the reboot command run from the console. The command returns as soon as it has executed the reboot action, which may be significantly before the domain actually reboots.

The exact behavior of a domain when it reboots is set by the on_reboot parameter in the domain's

XML

definition.

By default the hypervisor will try to pick a suitable shutdown method. To specify an alternative method, the --mode parameter can specify a comma separated list which includes "acpi", "agent", "initctl", "signal" and "paravirt". The order in which drivers will try each mode is undefined, and not related to the order specified to virsh. For strict control over ordering, use a single mode at a time and repeat the command.

reset domain

Reset a domain immediately without any guest shutdown. reset emulates the power reset button on a machine, where all guest hardware sees the

RST

line set and reinitializes internal state.

Note: Reset without any guest

OS

shutdown risks data loss.

restore state-file [--bypass-cache] [--xml file] [{--running | --paused}]

Restores a domain from a virsh save state file. See save for more info.

If --bypass-cache is specified, the restore will avoid the file system cache, although this may slow down the operation.

--xml file is usually omitted, but can be used to supply an alternative

XML

file for use on the restored guest with changes only in the host-specific portions of the domain

XML.

For example, it can be used to account for file naming differences in underlying storage due to disk snapshots taken after the guest was saved.

Normally, restoring a saved image will use the state recorded in the save image to decide between running or paused; passing either the --running or --paused flag will allow overriding which state the domain should be started in.

Note: To avoid corrupting file system contents within the domain, you should not reuse the saved state file for a second restore unless you have also reverted all storage volumes back to the same contents as when the state file was created.

save domain state-file [--bypass-cache] [--xml file] [{--running | --paused}] [--verbose]

Saves a running domain (

RAM,

but not disk state) to a state file so that it can be restored later. Once saved, the domain will no longer be running on the system, thus the memory allocated for the domain will be free for other domains to use. virsh restore restores from this state file. If --bypass-cache is specified, the save will avoid the file system cache, although this may slow down the operation.

The progress may be monitored using domjobinfo virsh command and canceled with domjobabort command (sent by another virsh instance). Another option is to send

SIGINT

(usually with "Ctrl-C") to the virsh process running save command. --verbose displays the progress of save.

This is roughly equivalent to doing a hibernate on a running computer, with all the same limitations. Open network connections may be severed upon restore, as

TCP

timeouts may have expired.

--xml file is usually omitted, but can be used to supply an alternative

XML

file for use on the restored guest with changes only in the host-specific portions of the domain

XML.

For example, it can be used to account for file naming differences that are planned to be made via disk snapshots of underlying storage after the guest is saved.

Normally, restoring a saved image will decide between running or paused based on the state the domain was in when the save was done; passing either the --running or --paused flag will allow overriding which state the restore should use.

Domain saved state files assume that disk images will be unchanged between the creation and restore point. For a more complete system restore point, where the disk state is saved alongside the memory state, see the snapshot family of commands.

save-image-define file xml [{--running | --paused}]

Update the domain

XML

that will be used when file is later used in the restore command. The xml argument must be a file name containing the alternative

XML,

with changes only in the host-specific portions of the domain

XML.

For example, it can be used to account for file naming differences resulting from creating disk snapshots of underlying storage after the guest was saved.

The save image records whether the domain should be restored to a running or paused state. Normally, this command does not alter the recorded state; passing either the --running or --paused flag will allow overriding which state the restore should use.

save-image-dumpxml file [--security-info]

Extract the domain

XML

that was in effect at the time the saved state file file was created with the save command. Using --security-info will also include security sensitive information.

save-image-edit file [{--running | --paused}]

Edit the

XML

configuration associated with a saved state file file created by the save command.

The save image records whether the domain should be restored to a running or paused state. Normally, this command does not alter the recorded state; passing either the --running or --paused flag will allow overriding which state the restore should use.

This is equivalent to:

 virsh save-image-dumpxml state-file > state-file.xml
 vi state-file.xml (or make changes with your other text editor)
 virsh save-image-define state-file state-file-xml

except that it does some error checking.

The editor used can be supplied by the $VISUAL or $EDITOR environment variables, and defaults to "vi".

schedinfo domain [[--config] [--live] | [--current]] [[--set] parameter=value]...

schedinfo [--weight number] [--cap number] domain

Allows you to show (and set) the domain scheduler parameters. The parameters available for each hypervisor are:

LXC

(posix scheduler) : cpu_shares, vcpu_period, vcpu_quota

QEMU/KVM

(posix scheduler): cpu_shares, vcpu_period, vcpu_quota, emulator_period, emulator_quota, iothread_quota, iothread_period

Xen (credit scheduler): weight, cap

ESX

(allocation scheduler): reservation, limit, shares

If --live is specified, set scheduler information of a running guest. If --config is specified, affect the next boot of a persistent guest. If --current is specified, affect the current guest state.

Note: The cpu_shares parameter has a valid value range of 0-262144; Negative values are wrapped to positive, and larger values are capped at the maximum. Therefore, -1 is a useful shorthand for 262144. On the Linux kernel, the values 0 and 1 are automatically converted to a minimal value of 2.

Note: The weight and cap parameters are defined only for the

XEN_CREDIT

scheduler.

Note: The vcpu_period, emulator_period, and iothread_period parameters have a valid value range of 1000-1000000 or 0, and the vcpu_quota, emulator_quota, and iothread_quota parameters have a valid value range of 1000-18446744073709551 or less than 0. The value 0 for either parameter is the same as not specifying that parameter.

screenshot domain [imagefilepath] [--screen screenID]

Takes a screenshot of a current domain console and stores it into a file. Optionally, if hypervisor supports more displays for a domain, screenID allows to specify which screen will be captured. It is the sequential number of screen. In case of multiple graphics cards, heads are enumerated before devices, e.g. having two graphics cards, both with four heads, screen

ID 5

addresses the second head on the second card.

send-key domain [--codeset codeset] [--holdtime holdtime] keycode...

Parse the keycode sequence as keystrokes to send to domain. Each keycode can either be a numeric value or a symbolic name from the corresponding codeset. If --holdtime is given, each keystroke will be held for that many milliseconds. The default codeset is linux, but use of the --codeset option allows other codesets to be chosen.

If multiple keycodes are specified, they are all sent simultaneously to the guest, and they may be received in random order. If you need distinct keypresses, you must use multiple send-key invocations.

linux

The numeric values are those defined by the Linux generic input event subsystem. The symbolic names match the corresponding Linux key constant macro names.

See virkeycode-linux(7) and virkeyname-linux(7)

xt

The numeric values are those defined by the original

XT

keyboard controller. No symbolic names are provided

See virkeycode-xt(7)

atset1

The numeric values are those defined by the

AT

keyboard controller, set 1 (aka

XT

compatible set). Extended keycoes from atset1 may differ from extended keycodes in the xt codeset. No symbolic names are provided

See virkeycode-atset1(7)

atset2

The numeric values are those defined by the

AT

keyboard controller, set 2. No symbolic names are provided

See virkeycode-atset2(7)

atset3

The numeric values are those defined by the

AT

keyboard controller, set 3 (aka

PS/2

compatible set). No symbolic names are provided

See virkeycode-atset3(7)

os_x

The numeric values are those defined by the OS-X keyboard input subsystem. The symbolic names match the corresponding OS-X key constant macro names

See virkeycode-osx(7) and virkeyname-osx(7)

xt_kbd

The numeric values are those defined by the Linux

KBD

device. These are a variant on the original

XT

codeset, but often with different encoding for extended keycodes. No symbolic names are provided.

See virkeycode-xtkbd(7)

win32

The numeric values are those defined by the Win32 keyboard input subsystem. The symbolic names match the corresponding Win32 key constant macro names

See virkeycode-win32(7) and virkeyname-win32(7)

usb

The numeric values are those defined by the

USB HID

specification for keyboard input. No symbolic names are provided

See virkeycode-usb(7)

rfb

The numeric values are those defined by the

RFB

extension for sending raw keycodes. These are a variant on the

XT

codeset, but extended keycodes have the low bit of the second byte set, instead of the high bit of the first byte. No symbolic names are provided.

See virkeycode-rfb(7)

Examples
  # send three strokes 'k', 'e', 'y', using xt codeset. these
  # are all pressed simultaneously and may be received by the guest
  # in random order
  virsh send-key dom --codeset xt 37 18 21

  # send one stroke 'right-ctrl+C'
  virsh send-key dom KEY_RIGHTCTRL KEY_C

  # send a tab, held for 1 second
  virsh send-key --holdtime 1000 0xf

send-process-signal domain-id pid signame

Send a signal signame to the process identified by pid running in the virtual domain domain-id. The pid is a process

ID

in the virtual domain namespace.

The signame argument may be either an integer signal constant number, or one of the symbolic names:

    "nop", "hup", "int", "quit", "ill",
    "trap", "abrt", "bus", "fpe", "kill",
    "usr1", "segv", "usr2", "pipe", "alrm",
    "term", "stkflt", "chld", "cont", "stop",
    "tstp", "ttin", "ttou", "urg", "xcpu",
    "xfsz", "vtalrm", "prof", "winch", "poll",
    "pwr", "sys", "rt0", "rt1", "rt2", "rt3",
    "rt4", "rt5", "rt6", "rt7", "rt8", "rt9",
    "rt10", "rt11", "rt12", "rt13", "rt14", "rt15",
    "rt16", "rt17", "rt18", "rt19", "rt20", "rt21",
    "rt22", "rt23", "rt24", "rt25", "rt26", "rt27",
    "rt28", "rt29", "rt30", "rt31", "rt32"

The symbol name may optionally be prefixed with 'sig' or 'sig_' and may be in uppercase or lowercase.

Examples
  virsh send-process-signal myguest 1 15
  virsh send-process-signal myguest 1 term
  virsh send-process-signal myguest 1 sigterm
  virsh send-process-signal myguest 1 

SIG_HUP

setmem domain size [[--config] [--live] | [--current]]

Change the memory allocation for a guest domain. If --live is specified, perform a memory balloon of a running guest. If --config is specified, affect the next boot of a persistent guest. If --current is specified, affect the current guest state. Both --live and --config flags may be given, but --current is exclusive. If no flag is specified, behavior is different depending on hypervisor.

size is a scaled integer (see

NOTES

above); it defaults to kibibytes (blocks of 1024 bytes) unless you provide a suffix (and the older option name --kilobytes is available as a deprecated synonym) . Libvirt rounds up to the nearest kibibyte. Some hypervisors require a larger granularity than KiB, and requests that are not an even multiple will be rounded up. For example, vSphere/ESX rounds the parameter up to mebibytes (1024 kibibytes).

For Xen, you can only adjust the memory of a running domain if the domain is paravirtualized or running the

PV

balloon driver.

For

LXC,

the value being set is the cgroups value for limit_in_bytes or the maximum amount of user memory (including file cache). When viewing memory inside the container, this is the /proc/meminfo ``MemTotal'' value. When viewing the value from the host, use the virsh memtune command. In order to view the current memory in use and the maximum value allowed to set memory, use the virsh dominfo command.

set-user-password domain user password [--encrypted]

Set the password for the user account in the guest domain.

If --encrypted is specified, the password is assumed to be already encrypted by the method required by the guest

OS.

For

QEMU/KVM,

this requires the guest agent to be configured and running.

setmaxmem domain size [[--config] [--live] | [--current]]

Change the maximum memory allocation limit for a guest domain. If --live is specified, affect a running guest. If --config is specified, affect the next boot of a persistent guest. If --current is specified, affect the current guest state. Both --live and --config flags may be given, but --current is exclusive. If no flag is specified, behavior is different depending on hypervisor.

Some hypervisors such as

QEMU/KVM

don't support live changes (especially increasing) of the maximum memory limit. Even persistent configuration changes might not be performed with some hypervisors/configuration (e.g. on

NUMA

enabled domains on

QEMU

). For complex configuration changes use command edit instead).

size is a scaled integer (see

NOTES

above); it defaults to kibibytes (blocks of 1024 bytes) unless you provide a suffix (and the older option name --kilobytes is available as a deprecated synonym) . Libvirt rounds up to the nearest kibibyte. Some hypervisors require a larger granularity than KiB, and requests that are not an even multiple will be rounded up. For example, vSphere/ESX rounds the parameter up to mebibytes (1024 kibibytes).

memtune domain [--hard-limit size] [--soft-limit size] [--swap-hard-limit size] [--min-guarantee size] [[--config] [--live] | [--current]]

Allows you to display or set the domain memory parameters. Without flags, the current settings are displayed; with a flag, the appropriate limit is adjusted if supported by the hypervisor.

LXC

and

QEMU/KVM

support --hard-limit, --soft-limit, and --swap-hard-limit. --min-guarantee is supported only by

ESX

hypervisor. Each of these limits are scaled integers (see

NOTES

above), with a default of kibibytes (blocks of 1024 bytes) if no suffix is present. Libvirt rounds up to the nearest kibibyte. Some hypervisors require a larger granularity than KiB, and requests that are not an even multiple will be rounded up. For example, vSphere/ESX rounds the parameter up to mebibytes (1024 kibibytes).

If --live is specified, affect a running guest. If --config is specified, affect the next boot of a persistent guest. If --current is specified, affect the current guest state. Both --live and --config flags may be given, but --current is exclusive. If no flag is specified, behavior is different depending on hypervisor.

For

QEMU/KVM,

the parameters are applied to the

QEMU

process as a whole. Thus, when counting them, one needs to add up guest

RAM,

guest video

RAM,

and some memory overhead of

QEMU

itself. The last piece is hard to determine so one needs guess and try.

For

LXC,

the displayed hard_limit value is the current memory setting from the

XML

or the results from a virsh setmem command.

--hard-limit

The maximum memory the guest can use.

--soft-limit

The memory limit to enforce during memory contention.

--swap-hard-limit

The maximum memory plus swap the guest can use. This has to be more than hard-limit value provided.

--min-guarantee

The guaranteed minimum memory allocation for the guest.

Specifying -1 as a value for these limits is interpreted as unlimited.

perf domain [--enable eventSpec] [--disable eventSpec] [[--config] [--live] | [--current]]

Get the current perf events setting or enable/disable specific perf events for a guest domain.

Perf is a performance analyzing tool in Linux, and it can instrument

CPU

performance counters, tracepoints, kprobes, and uprobes (dynamic tracing). Perf supports a list of measurable events, and can measure events coming from different sources. For instance, some event are pure kernel counters, in this case they are called software events, including context-switches, minor-faults, etc.. Now dozens of events from different sources can be supported by perf.

Currently only

QEMU/KVM

supports this command. The --enable and --disable option combined with eventSpec can be used to enable or disable specific performance event. eventSpec is a string list of one or more events separated by commas. Valid event names are as follows:

Valid perf event names
  cmt              - A PQos (Platform Qos) feature to monitor the
                     usage of cache by applications running on the
                     platform.
  mbmt             - Provides a way to monitor the total system
                     memory bandwidth between one level of cache
                     and another.
  mbml             - Provides a way to limit the amount of data
                     (bytes/s) send through the memory controller
                     on the socket.
  cache_misses     - Provides the count of cache misses by
                     applications running on the platform.
  cache_references - Provides the count of cache hits by
                     applications running on th e platform.
  instructions     - Provides the count of instructions executed
                     by applications running on the platform.
  cpu_cycles       - Provides the count of cpu cycles
                     (total/elapsed). May be used with
                     instructions in order to get a cycles
                     per instruction.
  branch_instructions - Provides the count of branch instructions
                        executed by applications running on the
                        platform.
  branch_misses    - Provides the count of branch misses executed
                     by applications running on the platform.
  bus_cycles       - Provides the count of bus cycles executed
                     by applications running on the platform.
  stalled_cycles_frontend - Provides the count of stalled cpu
                            cycles in the frontend of the
                            instruction processor pipeline by
                            applications running on the platform.
  stalled_cycles_backend - Provides the count of stalled cpu
                           cycles in the backend of the
                           instruction processor pipeline by
                           applications running on the platform.
  ref_cpu_cycles   -  Provides the count of total cpu cycles
                      not affected by 

CPU

 frequency scaling by
                      applications running on the platform.
  cpu_clock - Provides the cpu clock time consumed by
              applications running on the platform.
  task_clock - Provides the task clock time consumed by
               applications running on the platform.
  page_faults - Provides the count of page faults by
                applications running on the platform.
  context_switches - Provides the count of context switches
                     by applications running on the platform.
  cpu_migrations - Provides the count cpu migrations by
                   applications running on the platform.
  page_faults_min - Provides the count minor page faults
                    by applications running on the platform.
  page_faults_maj - Provides the count major page faults
                    by applications running on the platform.
  alignment_faults - Provides the count alignment faults
                     by applications running on the platform.
  emulation_faults - Provides the count emulation faults
                     by applications running on the platform.

Note: The statistics can be retrieved using the domstats command using the --perf flag.

If --live is specified, affect a running guest. If --config is specified, affect the next boot of a persistent guest. If --current is specified, affect the current guest state. Both --live and --config flags may be given, but --current is exclusive. If no flag is specified, behavior is different depending on hypervisor.

blkiotune domain [--weight weight] [--device-weights device-weights] [--device-read-iops-sec device-read-iops-sec] [--device-write-iops-sec device-write-iops-sec] [--device-read-bytes-sec device-read-bytes-sec] [--device-write-bytes-sec device-write-bytes-sec] [[--config] [--live] | [--current]]

Display or set the blkio parameters.

QEMU/KVM

supports --weight. --weight is in range [100, 1000]. After kernel 2.6.39, the value could be in the range [10, 1000].

device-weights is a single string listing one or more device/weight pairs, in the format of /path/to/device,weight,/path/to/device,weight. Each weight is in the range [100, 1000], [10, 1000] after kernel 2.6.39, or the value 0 to remove that device from per-device listings. Only the devices listed in the string are modified; any existing per-device weights for other devices remain unchanged.

device-read-iops-sec is a single string listing one or more device/read_iops_sec pairs, int the format of /path/to/device,read_iops_sec,/path/to/device,read_iops_sec. Each read_iops_sec is a number which type is unsigned int, value 0 to remove that device from per-device listing. Only the devices listed in the string are modified; any existing per-device read_iops_sec for other devices remain unchanged.

device-write-iops-sec is a single string listing one or more device/write_iops_sec pairs, int the format of /path/to/device,write_iops_sec,/path/to/device,write_iops_sec. Each write_iops_sec is a number which type is unsigned int, value 0 to remove that device from per-device listing. Only the devices listed in the string are modified; any existing per-device write_iops_sec for other devices remain unchanged.

device-read-bytes-sec is a single string listing one or more device/read_bytes_sec pairs, int the format of /path/to/device,read_bytes_sec,/path/to/device,read_bytes_sec. Each read_bytes_sec is a number which type is unsigned long long, value 0 to remove that device from per-device listing. Only the devices listed in the string are modified; any existing per-device read_bytes_sec for other devices remain unchanged.

device-write-bytes-sec is a single string listing one or more device/write_bytes_sec pairs, int the format of /path/to/device,write_bytes_sec,/path/to/device,write_bytes_sec. Each write_bytes_sec is a number which type is unsigned long long, value 0 to remove that device from per-device listing. Only the devices listed in the string are modified; any existing per-device write_bytes_sec for other devices remain unchanged.

If --live is specified, affect a running guest. If --config is specified, affect the next boot of a persistent guest. If --current is specified, affect the current guest state. Both --live and --config flags may be given, but --current is exclusive. If no flag is specified, behavior is different depending on hypervisor.

setvcpus domain count [--maximum] [[--config] [--live] | [--current]] [--guest] [--hotpluggable]

Change the number of virtual CPUs active in a guest domain. By default, this command works on active guest domains. To change the settings for an inactive guest domain, use the --config flag.

The count value may be limited by host, hypervisor, or a limit coming from the original description of the guest domain. For Xen, you can only adjust the virtual CPUs of a running domain if the domain is paravirtualized.

If the --config flag is specified, the change is made to the stored

XML

configuration for the guest domain, and will only take effect when the guest domain is next started.

If --live is specified, the guest domain must be active, and the change takes place immediately. Both the --config and --live flags may be specified together if supported by the hypervisor. If this command is run before the guest has finished booting, the guest may fail to process the change.

If --current is specified, affect the current guest state.

When no flags are given, the --live flag is assumed and the guest domain must be active. In this situation it is up to the hypervisor whether the --config flag is also assumed, and therefore whether the

XML

configuration is adjusted to make the change persistent.

If --guest is specified, then the count of cpus is modified in the guest instead of the hypervisor. This flag is usable only for live domains and may require guest agent to be configured in the guest.

To allow adding vcpus to persistent definitions that can be later hotunplugged after the domain is booted it is necessary to specify the --hotpluggable flag. Vcpus added to live domains supporting vcpu unplug are automatically marked as hotpluggable.

The --maximum flag controls the maximum number of virtual cpus that can be hot-plugged the next time the domain is booted. As such, it must only be used with the --config flag, and not with the --live or the --current flag. Note that it may not be possible to change the maximum vcpu count if the processor topology is specified for the guest.

setvcpu domain vcpulist [--enable] | [--disable] [[--live] [--config] | [--current]]

Change state of individual vCPUs using hot(un)plug mechanism.

See vcpupin for information on format of vcpulist. Hypervisor drivers may require that vcpulist contains exactly vCPUs belonging to one hotpluggable entity. This is usually just a single vCPU but certain architectures such as ppc64 require a full core to be specified at once.

Note that hypervisors may refuse to disable certain vcpus such as vcpu 0 or others.

If --live is specified, affect a running domain. If --config is specified, affect the next startup of a persistent domain. If --current is specified, affect the current domain state. This is the default. Both --live and --config flags may be given, but --current is exclusive.

shutdown domain [--mode MODE-LIST]

Gracefully shuts down a domain. This coordinates with the domain

OS

to perform graceful shutdown, so there is no guarantee that it will succeed, and may take a variable length of time depending on what services must be shutdown in the domain.

The exact behavior of a domain when it shuts down is set by the on_poweroff parameter in the domain's

XML

definition.

If domain is transient, then the metadata of any snapshots will be lost once the guest stops running, but the snapshot contents still exist, and a new domain with the same name and

UUID

can restore the snapshot metadata with snapshot-create.

By default the hypervisor will try to pick a suitable shutdown method. To specify an alternative method, the --mode parameter can specify a comma separated list which includes "acpi", "agent", "initctl", "signal" and "paravirt". The order in which drivers will try each mode is undefined, and not related to the order specified to virsh. For strict control over ordering, use a single mode at a time and repeat the command.

start domain-name-or-uuid [--console] [--paused] [--autodestroy] [--bypass-cache] [--force-boot] [--pass-fds N,M,...]

Start a (previously defined) inactive domain, either from the last managedsave state, or via a fresh boot if no managedsave state is present. The domain will be paused if the --paused option is used and supported by the driver; otherwise it will be running. If --console is requested, attach to the console after creation. If --autodestroy is requested, then the guest will be automatically destroyed when virsh closes its connection to libvirt, or otherwise exits. If --bypass-cache is specified, and managedsave state exists, the restore will avoid the file system cache, although this may slow down the operation. If --force-boot is specified, then any managedsave state is discarded and a fresh boot occurs.

If --pass-fds is specified, the argument is a comma separated list of open file descriptors which should be pass on into the guest. The file descriptors will be re-numbered in the guest, starting from 3. This is only supported with container based virtualization.

suspend domain

Suspend a running domain. It is kept in memory but won't be scheduled anymore.

resume domain

Moves a domain out of the suspended state. This will allow a previously suspended domain to now be eligible for scheduling by the underlying hypervisor.

dompmsuspend domain target [--duration]

Suspend a running domain into one of these states (possible target values):
    mem equivalent of S3 

ACPI

 state
    disk equivalent of S4 

ACPI

 state
    hybrid 

RAM

 is saved to disk but not powered off

The --duration argument specifies number of seconds before the domain is woken up after it was suspended (see also dompmwakeup). Default is 0 for unlimited suspend time. (This feature isn't currently supported by any hypervisor driver and 0 should be used.).

Note that this command requires a guest agent configured and running in the domain's guest

OS.

Beware that at least for

QEMU,

the domain's process will be terminated when target disk is used and a new process will be launched when libvirt is asked to wake up the domain. As a result of this, any runtime changes, such as device hotplug or memory settings, are lost unless such changes were made with --config flag.

dompmwakeup domain

Wakeup a domain from pmsuspended state (either suspended by dompmsuspend or from the guest itself). Injects a wakeup into the guest that is in pmsuspended state, rather than waiting for the previously requested duration (if any) to elapse. This operation doesn't not necessarily fail if the domain is running.

ttyconsole domain

Output the device used for the

TTY

console of the domain. If the information is not available the processes will provide an exit code of 1.

undefine domain [--managed-save] [--snapshots-metadata] [--nvram] [--keep-nvram] [ {--storage volumes | --remove-all-storage [--delete-snapshots]} --wipe-storage]

Undefine a domain. If the domain is running, this converts it to a transient domain, without stopping it. If the domain is inactive, the domain configuration is removed.

The --managed-save flag guarantees that any managed save image (see the managedsave command) is also cleaned up. Without the flag, attempts to undefine a domain with a managed save image will fail.

The --snapshots-metadata flag guarantees that any snapshots (see the snapshot-list command) are also cleaned up when undefining an inactive domain. Without the flag, attempts to undefine an inactive domain with snapshot metadata will fail. If the domain is active, this flag is ignored.

--nvram and --keep-nvram specify accordingly to delete or keep nvram (/domain/os/nvram/) file. If the domain has an nvram file and the flags are omitted, the undefine will fail.

The --storage flag takes a parameter volumes, which is a comma separated list of volume target names or source paths of storage volumes to be removed along with the undefined domain. Volumes can be undefined and thus removed only on inactive domains. Volume deletion is only attempted after the domain is undefined; if not all of the requested volumes could be deleted, the error message indicates what still remains behind. If a volume path is not found in the domain definition, it's treated as if the volume was successfully deleted. Only volumes managed by libvirt in storage pools can be removed this way. (See domblklist for list of target names associated to a domain). Example: --storage vda,/path/to/storage.img

The --remove-all-storage flag specifies that all of the domain's storage volumes should be deleted.

The --delete-snapshots flag specifies that any snapshots associated with the storage volume should be deleted as well. Requires the --remove-all-storage flag to be provided. Not all storage drivers support this option, presently only rbd.

The flag --wipe-storage specifies that the storage volumes should be wiped before removal.

NOTE:

For an inactive domain, the domain name or

UUID

must be used as the domain.

vcpucount domain [{--maximum | --active} {--config | --live | --current}] [--guest]

Print information about the virtual cpu counts of the given domain. If no flags are specified, all possible counts are listed in a table; otherwise, the output is limited to just the numeric value requested. For historical reasons, the table lists the label ``current'' on the rows that can be queried in isolation via the --active flag, rather than relating to the --current flag.

--maximum requests information on the maximum cap of vcpus that a domain can add via setvcpus, while --active shows the current usage; these two flags cannot both be specified. --config requires a persistent domain and requests information regarding the next time the domain will be booted, --live requires a running domain and lists current values, and --current queries according to the current state of the domain (corresponding to --live if running, or --config if inactive); these three flags are mutually exclusive.

If --guest is specified, then the count of cpus is reported from the perspective of the guest. This flag is usable only for live domains and may require guest agent to be configured in the guest.

vcpuinfo domain [--pretty]

Returns basic information about the domain virtual CPUs, like the number of vCPUs, the running time, the affinity to physical processors.

With --pretty, cpu affinities are shown as ranges.

An example output is

 $ virsh vcpuinfo fedora
 VCPU:           0
 CPU:            0
 State:          running
 CPU time:       7,0s
 CPU Affinity:   yyyy

 VCPU:           1
 CPU:            1
 State:          running
 CPU time:       0,7s
 CPU Affinity:   yyyy

STATES

The State field displays the current operating state of a virtual

CPU

offline

The virtual

CPU

is offline and not usable by the domain. This state is not supported by all hypervisors.

running

The virtual

CPU

is available to the domain and is operating.

blocked

The virtual

CPU

is available to the domain but is waiting for a resource. This state is not supported by all hypervisors, in which case running may be reported instead.

no state

The virtual

CPU

state could not be determined. This could happen if the hypervisor is newer than virsh.

N/A

There's no information about the virtual

CPU

state available. This can be the case if the domain is not running or the hypervisor does not report the virtual

CPU

state.

vcpupin domain [vcpu] [cpulist] [[--live] [--config] | [--current]]

Query or change the pinning of domain VCPUs to host physical CPUs. To pin a single vcpu, specify cpulist; otherwise, you can query one vcpu or omit vcpu to list all at once.

cpulist is a list of physical

CPU

numbers. Its syntax is a comma separated list and a special markup using '-' and '^' (ex. '0-4', '0-3,^2') can also be allowed. The '-' denotes the range and the '^' denotes exclusive. For pinning the vcpu to all physical cpus specify 'r' as a cpulist. If --live is specified, affect a running guest. If --config is specified, affect the next boot of a persistent guest. If --current is specified, affect the current guest state. Both --live and --config flags may be given if cpulist is present, but --current is exclusive. If no flag is specified, behavior is different depending on hypervisor.

Note: The expression is sequentially evaluated, so ``0-15,^8'' is identical to ``9-14,0-7,15'' but not identical to ``^8,0-15''.

emulatorpin domain [cpulist] [[--live] [--config] | [--current]]

Query or change the pinning of domain's emulator threads to host physical CPUs.

See vcpupin for cpulist.

If --live is specified, affect a running guest. If --config is specified, affect the next boot of a persistent guest. If --current is specified, affect the current guest state. Both --live and --config flags may be given if cpulist is present, but --current is exclusive. If no flag is specified, behavior is different depending on hypervisor.

guestvcpus domain [[--enable] | [--disable]] [cpulist]

Query or change state of vCPUs from guest's point of view using the guest agent. When invoked without cpulist the guest is queried for available guest vCPUs, their state and possibility to be offlined.

If cpulist is provided then one of --enable or --disable must be provided too. The desired operation is then executed on the domain.

See vcpupin for information on cpulist.

vncdisplay domain

Output the

IP

address and port number for the

VNC

display. If the information is not available the processes will provide an exit code of 1.

DEVICE COMMANDS

The following commands manipulate devices associated to domains. The domain can be specified as a short integer, a name or a full To better understand the values allowed as options for the command reading the documentation at <libvirt.org/formatdomain.html> on the format of the device sections to get the most accurate set of accepted values.

attach-device domain

FILE

[[[--live] [--config] | [--current]] | [--persistent]]

Attach a device to the domain, using a device definition in an

XML

file using a device definition element such as <disk> or <interface> as the top-level element. See the documentation at <libvirt.org/formatdomain.html#elementsDevices> to learn about libvirt

XML

format for a device. If --config is specified the command alters the persistent domain configuration with the device attach taking effect the next time libvirt starts the domain. For cdrom and floppy devices, this command only replaces the media within an existing device; consider using update-device for this usage. For passthrough host devices, see also nodedev-detach, needed if the

PCI

device does not use managed mode.

If --live is specified, affect a running domain. If --config is specified, affect the next startup of a persistent domain. If --current is specified, affect the current domain state. Both --live and --config flags may be given, but --current is exclusive. When no flag is specified legacy

API

is used whose behavior depends on the hypervisor driver.

For compatibility purposes, --persistent behaves like --config for an offline domain, and like --live --config for a running domain.

Note: using of partial device definition

XML

files may lead to unexpected results as some fields may be autogenerated and thus match devices other than expected.

attach-disk domain source target [[[--live] [--config] | [--current]] | [--persistent]] [--targetbus bus] [--driver driver] [--subdriver subdriver] [--iothread iothread] [--cache cache] [--io io] [--type type] [--mode mode] [--sourcetype sourcetype] [--serial serial] [--wwn wwn] [--rawio] [--address address] [--multifunction] [--print-xml]

Attach a new disk device to the domain. source is path for the files and devices. target controls the bus or device under which the disk is exposed to the guest

OS.

It indicates the ``logical'' device name; the optional targetbus attribute specifies the type of disk device to emulate; possible values are driver specific, with typical values being ide, scsi, virtio, xen, usb, sata, or sd, if omitted, the bus type is inferred from the style of the device name (e.g. a device named 'sda' will typically be exported using a

SCSI

bus). driver can be file, tap or phy for the Xen hypervisor depending on the kind of access; or qemu for the

QEMU

emulator. Further details to the driver can be passed using subdriver. For Xen subdriver can be aio, while for

QEMU

subdriver should match the format of the disk source, such as raw or qcow2. Hypervisor default will be used if subdriver is not specified. However, the default may not be correct, esp. for

QEMU

as for security reasons it is configured not to detect disk formats. type can indicate lun, cdrom or floppy as alternative to the disk default, although this use only replaces the media within the existing virtual cdrom or floppy device; consider using update-device for this usage instead. mode can specify the two specific mode readonly or shareable. sourcetype can indicate the type of source (block|file) cache can be one of ``default'', ``none'', ``writethrough'', ``writeback'', ``directsync'' or ``unsafe''. io controls specific policies on I/O;

QEMU

guests support ``threads'' and ``native''. iothread is the number within the range of domain IOThreads to which this disk may be attached (

QEMU

only). serial is the serial of disk device. wwn is the wwn of disk device. rawio indicates the disk needs rawio capability. address is the address of disk device in the form of pci:domain.bus.slot.function, scsi:controller.bus.unit, ide:controller.bus.unit or ccw:cssid.ssid.devno. Virtio-ccw devices must have their cssid set to 0xfe. multifunction indicates specified pci address is a multifunction pci device address.

If --print-xml is specified, then the

XML

of the disk that would be attached is printed instead.

If --live is specified, affect a running domain. If --config is specified, affect the next startup of a persistent domain. If --current is specified, affect the current domain state. Both --live and --config flags may be given, but --current is exclusive. When no flag is specified legacy

API

is used whose behavior depends on the hypervisor driver.

For compatibility purposes, --persistent behaves like --config for an offline domain, and like --live --config for a running domain. Likewise, --shareable is an alias for --mode shareable.

attach-interface domain type source [[[--live] [--config] | [--current]] | [--persistent]] [--target target] [--mac mac] [--script script] [--model model] [--inbound average,peak,burst,floor] [--outbound average,peak,burst] [--managed] [--print-xml]

Attach a new network interface to the domain.

type can be one of the:

network to indicate connection via a libvirt virtual network,

bridge to indicate connection via a bridge device on the host,

direct to indicate connection directly to one of the host's network interfaces or bridges,

hostdev to indicate connection using a passthrough of

PCI

device on the host.

source indicates the source of the connection. The source depends on the type of the interface:

network name of the virtual network,

bridge the name of the bridge device,

direct the name of the host's interface or bridge,

hostdev the

PCI

address of the host's interface formatted as domain:bus:slot.function.

--target is used to specify the tap/macvtap device to be used to connect the domain to the source. Names starting with 'vnet' are considered as auto-generated and are blanked out/regenerated each time the interface is attached.

--mac specifies the

MAC

address of the network interface; if a

MAC

address is not given, a new address will be automatically generated (and stored in the persistent configuration if ``--config'' is given on the command line).

--script is used to specify a path to a custom script to be called while attaching to a bridge - this will be called instead of the default script not in addition to it. This is valid only for interfaces of bridge type and only for Xen domains.

--model specifies the network device model to be presented to the domain.

--inbound and --outbound control the bandwidth of the interface. At least one from the average, floor pair must be specified. The other two peak and burst are optional, so ``average,peak'', ``average,,burst'', ``average,,,floor'', ``average'' and ``,,,floor'' are also legal. Values for average, floor and peak are expressed in kilobytes per second, while burst is expressed in kilobytes in a single burst at peak speed as described in the Network

XML

documentation at <libvirt.org/formatnetwork.html#elementQoS>.

--managed is usable only for hostdev type and tells libvirt that the interface should be managed, which means detached and reattached from/to the host by libvirt.

If --print-xml is specified, then the

XML

of the interface that would be attached is printed instead.

If --live is specified, affect a running domain. If --config is specified, affect the next startup of a persistent domain. If --current is specified, affect the current domain state. Both --live and --config flags may be given, but --current is exclusive. When no flag is specified legacy

API

is used whose behavior depends on the hypervisor driver.

For compatibility purposes, --persistent behaves like --config for an offline domain, and like --live --config for a running domain.

Note: the optional target value is the name of a device to be created as the back-end on the node. If not provided a device named ``vnetN'' or ``vifN'' will be created automatically.

detach-device domain

FILE

[[[--live] [--config] | [--current]] | [--persistent]]

Detach a device from the domain, takes the same kind of

XML

descriptions as command attach-device. For passthrough host devices, see also nodedev-reattach, needed if the device does not use managed mode.

Note: The supplied

XML

description of the device should be as specific as its definition in the domain

XML.

The set of attributes used to match the device are internal to the drivers. Using a partial definition, or attempting to detach a device that is not present in the domain

XML,

but shares some specific attributes with one that is present, may lead to unexpected results.

If --live is specified, affect a running domain. If --config is specified, affect the next startup of a persistent domain. If --current is specified, affect the current domain state. Both --live and --config flags may be given, but --current is exclusive. When no flag is specified legacy

API

is used whose behavior depends on the hypervisor driver.

For compatibility purposes, --persistent behaves like --config for an offline domain, and like --live --config for a running domain.

Note that older versions of virsh used --config as an alias for --persistent.

detach-disk domain target [[[--live] [--config] | [--current]] | [--persistent]]

Detach a disk device from a domain. The target is the device as seen from the domain.

If --live is specified, affect a running domain. If --config is specified, affect the next startup of a persistent domain. If --current is specified, affect the current domain state. Both --live and --config flags may be given, but --current is exclusive. When no flag is specified legacy

API

is used whose behavior depends on the hypervisor driver.

For compatibility purposes, --persistent behaves like --config for an offline domain, and like --live --config for a running domain.

Note that older versions of virsh used --config as an alias for --persistent.

detach-interface domain type [--mac mac] [[[--live] [--config] | [--current]] | [--persistent]]

Detach a network interface from a domain. type can be either network to indicate a physical network device or bridge to indicate a bridge to a device. It is recommended to use the mac option to distinguish between the interfaces if more than one are present on the domain.

If --live is specified, affect a running domain. If --config is specified, affect the next startup of a persistent domain. If --current is specified, affect the current domain state. Both --live and --config flags may be given, but --current is exclusive. When no flag is specified legacy

API

is used whose behavior depends on the hypervisor driver.

For compatibility purposes, --persistent behaves like --config for an offline domain, and like --live --config for a running domain.

Note that older versions of virsh used --config as an alias for --persistent.

update-device domain file [--force] [[[--live] [--config] | [--current]] | [--persistent]]

Update the characteristics of a device associated with domain, based on the device definition in an

XML

file. The --force option can be used to force device update, e.g., to eject a CD-ROM even if it is locked/mounted in the domain. See the documentation at <libvirt.org/formatdomain.html#elementsDevices> to learn about libvirt

XML

format for a device.

If --live is specified, affect a running domain. If --config is specified, affect the next startup of a persistent domain. If --current is specified, affect the current domain state. Both --live and --config flags may be given, but --current is exclusive. Not specifying any flag is the same as specifying --current.

For compatibility purposes, --persistent behaves like --config for an offline domain, and like --live --config for a running domain.

Note that older versions of virsh used --config as an alias for --persistent.

Note: using of partial device definition

XML

files may lead to unexpected results as some fields may be autogenerated and thus match devices other than expected.

change-media domain path [--eject] [--insert] [--update] [source] [--force] [[--live] [--config] | [--current]] [--print-xml] [--block]

Change media of

CDROM

or floppy drive. path can be the fully-qualified path or the unique target name (<target dev='hdc'>) of the disk device. source specifies the path of the media to be inserted or updated. Flag --block allows to set the backing type in case a block device is used as media for the

CDROM

or floppy drive instead of a file.

--eject indicates the media will be ejected. --insert indicates the media will be inserted. source must be specified. If the device has source (e.g. <source file='media'>), and source is not specified, --update is equal to --eject. If the device has no source, and source is specified, --update is equal to --insert. If the device has source, and source is specified, --update behaves like combination of --eject and --insert. If none of --eject, --insert, and --update is specified, --update is used by default. The --force option can be used to force media changing. If --live is specified, alter live configuration of running guest. If --config is specified, alter persistent configuration, effect observed on next boot. --current can be either or both of live and config, depends on the hypervisor's implementation. Both --live and --config flags may be given, but --current is exclusive. If no flag is specified, behavior is different depending on hypervisor. If --print-xml is specified, the

XML

that would be used to change media is printed instead of changing the media.

NODEDEV COMMANDS

The following commands manipulate host devices that are intended to be passed through to guest domains via <hostdev> elements in a domain's <devices> section. A node device key is generally specified by the bus name followed by its address, using underscores between all components, such as pci_0000_00_02_1, usb_1_5_3, or net_eth1_00_27_13_6a_fe_00. The nodedev-list gives the full list of host devices that are known to libvirt, although this includes devices that cannot be assigned to a guest (for example, attempting to detach the device that controls the host's hard disk controller where the guest's disk images live could cause the host system to lock up or reboot).

For more information on node device definition see: <libvirt.org/formatnode.html>.

Passthrough devices cannot be simultaneously used by the host and its guest domains, nor by multiple active guests at once. If the <hostdev> description of a

device includes the attribute managed='yes', and the hypervisor driver supports it, then the device is in managed mode, and attempts to use that passthrough device in an active guest will automatically behave as if nodedev-detach (guest start, device hot-plug) and nodedev-reattach (guest stop, device hot-unplug) were called at the right points. If a device is not marked as managed, then it must manually be detached before guests can use it, and manually reattached to be returned to the host. Also, if a device is manually detached, then the host does not regain control of the device without a matching reattach, even if the guests use the device in managed mode.

nodedev-create

FILE

Create a device on the host node that can then be assigned to virtual machines. Normally, libvirt is able to automatically determine which host nodes are available for use, but this allows registration of host hardware that libvirt did not automatically detect. file contains xml for a top-level <device> description of a node device.

nodedev-destroy device

Destroy (stop) a device on the host. device can be either device name or wwn pair in ``wwnn,wwpn'' format (only works for vHBA currently). Note that this makes libvirt quit managing a host device, and may even make that device unusable by the rest of the physical host until a reboot.

nodedev-detach nodedev [--driver backend_driver]

Detach nodedev from the host, so that it can safely be used by guests via <hostdev> passthrough. This is reversed with nodedev-reattach, and is done automatically for managed devices.

Different backend drivers expect the device to be bound to different dummy devices. For example,

QEMU

's ``kvm'' backend driver (the default) expects the device to be bound to pci-stub, but its ``vfio'' backend driver expects the device to be bound to vfio-pci. The --driver parameter can be used to specify the desired backend driver.

nodedev-dumpxml device

Dump a <device>

XML

representation for the given node device, including such information as the device name, which bus owns the device, the vendor and product id, and any capabilities of the device usable by libvirt (such as whether device reset is supported). device can be either device name or wwn pair in ``wwnn,wwpn'' format (only works for

HBA

).

nodedev-list cap --tree

List all of the devices available on the node that are known by libvirt. cap is used to filter the list by capability types, the types must be separated by comma, e.g. --cap pci,scsi. Valid capability types include 'system', 'pci', 'usb_device', 'usb', 'net', 'scsi_host', 'scsi_target', 'scsi', 'storage', 'fc_host', 'vports', 'scsi_generic', 'drm', 'mdev', 'mdev_types', 'ccw'. If --tree is used, the output is formatted in a tree representing parents of each node. cap and --tree are mutually exclusive.

nodedev-reattach nodedev

Declare that nodedev is no longer in use by any guests, and that the host can resume normal use of the device. This is done automatically for

PCI

devices in managed mode and

USB

devices, but must be done explicitly to match any explicit nodedev-detach.

nodedev-reset nodedev

Trigger a device reset for nodedev, useful prior to transferring a node device between guest passthrough or the host. Libvirt will often do this action implicitly when required, but this command allows an explicit reset when needed.

nodedev-event {[nodedev] event [--loop] [--timeout seconds] [--timestamp] | --list}

Wait for a class of node device events to occur, and print appropriate details of events as they happen. The events can optionally be filtered by nodedev. Using --list as the only argument will provide a list of possible event values known by this client, although the connection might not allow registering for all these events.

By default, this command is one-shot, and returns success once an event occurs; you can send

SIGINT

(usually via "Ctrl-C") to quit immediately. If --timeout is specified, the command gives up waiting for events after seconds have elapsed. With --loop, the command prints all events until a timeout or interrupt key.

When --timestamp is used, a human-readable timestamp will be printed before the event.

VIRTUAL NETWORK COMMANDS

The following commands manipulate networks. Libvirt has the capability to define virtual networks which can then be used by domains and linked to actual network devices. For more detailed information about this feature see the documentation at <libvirt.org/formatnetwork.html> . Many of the commands for virtual networks are similar to the ones used for domains, but the way to name a virtual network is either by its name or

net-autostart network [--disable]

Configure a virtual network to be automatically started at boot. The --disable option disable autostarting.

net-create file

Create a transient (temporary) virtual network from an

XML

file and instantiate (start) the network. See the documentation at <libvirt.org/formatnetwork.html> to get a description of the

XML

network format used by libvirt.

net-define file

Define an inactive persistent virtual network or modify an existing persistent one from the

XML

file.

net-destroy network

Destroy (stop) a given transient or persistent virtual network specified by its name or

UUID.

This takes effect immediately.

net-dumpxml network [--inactive]

Output the virtual network information as an

XML

dump to stdout. If --inactive is specified, then physical functions are not expanded into their associated virtual functions.

net-edit network

Edit the

XML

configuration file for a network.

This is equivalent to:

 virsh net-dumpxml --inactive network > network.xml
 vi network.xml (or make changes with your other text editor)
 virsh net-define network.xml

except that it does some error checking.

The editor used can be supplied by the $VISUAL or $EDITOR environment variables, and defaults to "vi".

net-event {[network] event [--loop] [--timeout seconds] [--timestamp] | --list}

Wait for a class of network events to occur, and print appropriate details of events as they happen. The events can optionally be filtered by network. Using --list as the only argument will provide a list of possible event values known by this client, although the connection might not allow registering for all these events.

By default, this command is one-shot, and returns success once an event occurs; you can send

SIGINT

(usually via "Ctrl-C") to quit immediately. If --timeout is specified, the command gives up waiting for events after seconds have elapsed. With --loop, the command prints all events until a timeout or interrupt key.

When --timestamp is used, a human-readable timestamp will be printed before the event.

net-info network

Returns basic information about the network object.

net-list [--inactive | --all] { [--table] | --name | --uuid } [--persistent] [<--transient>] [--autostart] [<--no-autostart>]

Returns the list of active networks, if --all is specified this will also include defined but inactive networks, if --inactive is specified only the inactive ones will be listed. You may also want to filter the returned networks by --persistent to list the persistent ones, --transient to list the transient ones, --autostart to list the ones with autostart enabled, and --no-autostart to list the ones with autostart disabled.

If --name is specified, network names are printed instead of the table formatted one per line. If --uuid is specified network's

UUID

's are printed instead of names. Flag --table specifies that the legacy table-formatted output should be used. This is the default. All of these are mutually exclusive.

NOTE:

When talking to older servers, this command is forced to use a series of

API

calls with an inherent race, where a pool might not be listed or might appear more than once if it changed state between calls while the list was being collected. Newer servers do not have this problem.

net-name network-UUID

Convert a network

UUID

to network name.

net-start network

Start a (previously defined) inactive network.

net-undefine network

Undefine the configuration for a persistent network. If the network is active, make it transient.

net-uuid network-name

Convert a network name to network

UUID.

net-update network command section xml [--parent-index index] [[--live] [--config] | [--current]]

Update the given section of an existing network definition, with the changes optionally taking effect immediately, without needing to destroy and re-start the network.

command is one of ``add-first'', ``add-last'', ``add'' (a synonym for add-last), ``delete'', or ``modify''.

section is one of ``bridge'', ``domain'', ``ip'', ``ip-dhcp-host'', ``ip-dhcp-range'', ``forward'', ``forward-interface'', ``forward-pf'', ``portgroup'', ``dns-host'', ``dns-txt'', or ``dns-srv'', each section being named by a concatenation of the xml element hierarchy leading to the element being changed. For example, ``ip-dhcp-host'' will change a <host> element that is contained inside a <dhcp> element inside an <ip> element of the network.

xml is either the text of a complete xml element of the type being changed (e.g. ``<host mac=''00:11:22:33:44:55' ip='1.2.3.4'/>``, or the name of a file that contains a complete xml element. Disambiguation is done by looking at the first character of the provided text - if the first character is ''<``, it is xml text, if the first character is not ''<", it is the name of a file that contains the xml text to be used.

The --parent-index option is used to specify which of several parent elements the requested element is in (0-based). For example, a dhcp <host> element could be in any one of multiple <ip> elements in the network; if a parent-index isn't provided, the ``most appropriate'' <ip> element will be selected (usually the only one that already has a <dhcp> element), but if --parent-index is given, that particular instance of <ip> will get the modification.

If --live is specified, affect a running network. If --config is specified, affect the next startup of a persistent network. If --current is specified, affect the current network state. Both --live and --config flags may be given, but --current is exclusive. Not specifying any flag is the same as specifying --current.

net-dhcp-leases network [mac]

Get a list of dhcp leases for all network interfaces connected to the given virtual network or limited output just for one interface if mac is specified.

INTERFACE COMMANDS

The following commands manipulate host interfaces. Often, these host interfaces can then be used by name within domain <interface> elements (such as a system-created bridge interface), but there is no requirement that host interfaces be tied to any particular guest configuration at all.

Many of the commands for host interfaces are similar to the ones used for domains, and the way to name an interface is either by its name or its

address. However, using a address for an iface argument only works when that address is unique (if an interface and a bridge share the same address, which is often the case, then using that address results in an error due to ambiguity, and you must resort to a name instead).

iface-bridge interface bridge [--no-stp] [delay] [--no-start]

Create a bridge device named bridge, and attach the existing network device interface to the new bridge. The new bridge defaults to starting immediately, with

STP

enabled and a delay of 0; these settings can be altered with --no-stp, --no-start, and an integer number of seconds for delay. All

IP

address configuration of interface will be moved to the new bridge device.

See also iface-unbridge for undoing this operation.

iface-define file

Define an inactive persistent physical host interface or modify an existing persistent one from the

XML

file.

iface-destroy interface

Destroy (stop) a given host interface, such as by running ``if-down'' to disable that interface from active use. This takes effect immediately.

iface-dumpxml interface [--inactive]

Output the host interface information as an

XML

dump to stdout. If --inactive is specified, then the output reflects the persistent state of the interface that will be used the next time it is started.

iface-edit interface

Edit the

XML

configuration file for a host interface.

This is equivalent to:

 virsh iface-dumpxml iface > iface.xml
 vi iface.xml (or make changes with your other text editor)
 virsh iface-define iface.xml

except that it does some error checking.

The editor used can be supplied by the $VISUAL or $EDITOR environment variables, and defaults to "vi".

iface-list [--inactive | --all]

Returns the list of active host interfaces. If --all is specified this will also include defined but inactive interfaces. If --inactive is specified only the inactive ones will be listed.

iface-name interface

Convert a host interface

MAC

to interface name, if the

MAC

address is unique among the host's interfaces.

interface specifies the interface

MAC

address.

iface-mac interface

Convert a host interface name to

MAC

address.

interface specifies the interface name.

iface-start interface

Start a (previously defined) host interface, such as by running ``if-up''.

iface-unbridge bridge [--no-start]

Tear down a bridge device named bridge, releasing its underlying interface back to normal usage, and moving all

IP

address configuration from the bridge device to the underlying device. The underlying interface is restarted unless --no-start is present; this flag is present for symmetry, but generally not recommended.

See also iface-bridge for creating a bridge.

iface-undefine interface

Undefine the configuration for an inactive host interface.

iface-begin

Create a snapshot of current host interface settings, which can later be committed (iface-commit) or restored (iface-rollback). If a snapshot already exists, then this command will fail until the previous snapshot has been committed or restored. Undefined behavior results if any external changes are made to host interfaces outside of the libvirt

API

between the beginning of a snapshot and its eventual commit or rollback.

iface-commit

Declare all changes since the last iface-begin as working, and delete the rollback point. If no interface snapshot has already been started, then this command will fail.

iface-rollback

Revert all host interface settings back to the state recorded in the last iface-begin. If no interface snapshot has already been started, then this command will fail. Rebooting the host also serves as an implicit rollback point.

STORAGE POOL COMMANDS

The following commands manipulate storage pools. Libvirt has the capability to manage various storage solutions, including files, raw partitions, and domain-specific formats, used to provide the storage volumes visible as devices within virtual machines. For more detailed information about this feature, see the documentation at <libvirt.org/formatstorage.html> . Many of the commands for pools are similar to the ones used for domains.

find-storage-pool-sources type [srcSpec]

Returns

XML

describing all possible available storage pool sources that could be used to create or define a storage pool of a given type. If srcSpec is provided, it is a file that contains

XML

to further restrict the query for pools.

Not all storage pools support discovery in this manner. Furthermore, for those that do support discovery, only specific

XML

elements are required in order to return valid data, while other elements and even attributes of some elements are ignored since they are not necessary to find the pool based on the search criteria. The following lists the supported type options and the expected minimal

XML

elements used to perform the search.

For a ``netfs'' or ``gluster'' pool, the minimal expected

XML

required is the <host> element with a ``name'' attribute describing the

IP

address or hostname to be used to find the pool. The ``port'' attribute will be ignored as will any other provided

XML

elements in srcSpec.

For a ``logical'' pool, the contents of the srcSpec file are ignored, although if provided the file must at least exist.

For an ``iscsi'' pool, the minimal expect

XML

required is the <host> element with a ``name'' attribute describing the

IP

address or hostname to be used to find the pool (the iSCSI server address). Optionally, the ``port'' attribute may be provided, although it will default to 3260. Optionally, an <initiator>

XML

element with a ``name'' attribute may be provided to further restrict the iSCSI target search to a specific initiator for multi-iqn iSCSI storage pools.

find-storage-pool-sources-as type [host] [port] [initiator]

Rather than providing srcSpec

XML

file for find-storage-pool-sources use this command option in order to have virsh generate the query

XML

file using the optional arguments. The command will return the same output

XML

as find-storage-pool-sources.

Use host to describe a specific host to use for networked storage, such as netfs, gluster, and iscsi type pools.

Use port to further restrict which networked port to utilize for the connection if required by the specific storage backend, such as iscsi.

Use initiator to further restrict the iscsi type pool searches to specific target initiators.

pool-autostart pool-or-uuid [--disable]

Configure whether pool should automatically start at boot.

pool-build pool-or-uuid [--overwrite] [--no-overwrite]

Build a given pool.

Options --overwrite and --no-overwrite can only be used for pool-build a filesystem, disk, or logical pool.

For a file system pool if neither flag is specified, then pool-build just makes the target path directory and no attempt to run mkfs on the target volume device. If --no-overwrite is specified, it probes to determine if a filesystem already exists on the target device, returning an error if one exists or using mkfs to format the target device if not. If --overwrite is specified, mkfs is always executed and any existing data on the target device is overwritten unconditionally.

For a disk pool, if neither of them is specified or --no-overwrite is specified, pool-build will check the target volume device for existing filesystems or partitions before attempting to write a new label on the target volume device. If the target volume device already has a label, the command will fail. If --overwrite is specified, then no check will be made on the target volume device prior to writing a new label. Writing of the label uses the pool source format type or ``dos'' if not specified.

For a logical pool, if neither of them is specified or --no-overwrite is specified, pool-build will check the target volume devices for existing filesystems or partitions before attempting to initialize and format each device for usage by the logical pool. If any target volume device already has a label, the command will fail. If --overwrite is specified, then no check will be made on the target volume devices prior to initializing and formatting each device. Once all the target volume devices are properly formatted via pvcreate, the volume group will be created using all the devices.

pool-create file [--build] [[--overwrite] | [--no-overwrite]]

Create and start a pool object from the

XML

file.

[--build] [[--overwrite] | [--no-overwrite]] perform a pool-build after creation in order to remove the need for a follow-up command to build the pool. The --overwrite and --no-overwrite flags follow the same rules as pool-build. If just --build is provided, then pool-build is called with no flags.

pool-create-as name type [--source-host hostname] [--source-path path] [--source-dev path] [--source-name name] [--target path] [--source-format format] [--auth-type authtype --auth-username username --secret-usage usage] [[--adapter-name name] | [--adapter-wwnn --adapter-wwpn] [--adapter-parent parent]] [--build] [[--overwrite] | [--no-overwrite]] [--print-xml]

Create and start a pool object name from the raw parameters. If --print-xml is specified, then print the

XML

of the pool object without creating the pool. Otherwise, the pool has the specified type. When using pool-create-as for a pool of type ``disk'', the existing partitions found on the --source-dev path will be used to populate the disk pool. Therefore, it is suggested to use pool-define-as and pool-build with the --overwrite in order to properly initialize the disk pool.

[--source-host hostname] provides the source hostname for pools backed by storage from a remote server (pool types netfs, iscsi, rbd, sheepdog, gluster).

[--source-path path] provides the source directory path for pools backed by directories (pool type dir).

[--source-dev path] provides the source path for pools backed by physical devices (pool types fs, logical, disk, iscsi, zfs).

[--source-name name] provides the source name for pools backed by storage from a named element (pool types logical, rbd, sheepdog, gluster).

[--target path] is the path for the mapping of the storage pool into the host file system.

[--source-format format] provides information about the format of the pool (pool types fs, netfs, disk, logical).

[--auth-type authtype --auth-username username --secret-usage usage] provides the elements required to generate authentication credentials for the storage pool. The authtype is either chap for iscsi type pools or ceph for rbd type pools.

[--adapter-name name] defines the scsi_hostN adapter name to be used for the scsi_host adapter type pool.

[--adapter-wwnn --adapter-wwpn [--adapter-parent parent]] defines the wwnn and wwpn to be used for the fc_host adapter type pool. The parent optionally provides the name of the scsi_hostN node device to be used for the vHBA.

[--build] [[--overwrite] | [--no-overwrite]] perform a pool-build after creation in order to remove the need for a follow-up command to build the pool. The --overwrite and --no-overwrite flags follow the same rules as pool-build. If just --build is provided, then pool-build is called with no flags.

For a ``logical'' pool only [--name] needs to be provided. The [--source-name] if provided must match the Volume Group name. If not provided, one will be generated using the [--name]. If provided the [--target] is ignored and a target source is generated using the [--source-name] (or as generated from the [--name]).

pool-define file

Define an inactive persistent storage pool or modify an existing persistent one from the

XML

file.

pool-define-as name type [--source-host hostname] [--source-path path] [--source-dev path] [--source-name name] [--target path] [--source-format format] [--auth-type authtype --auth-username username --secret-usage usage] [[--adapter-name name] | [--adapter-wwnn --adapter-wwpn] [--adapter-parent parent]] [--print-xml]

Create, but do not start, a pool object name from the raw parameters. If --print-xml is specified, then print the

XML

of the pool object without defining the pool. Otherwise, the pool has the specified type.

Use the same arguments as pool-create-as, except for the --build, --overwrite, and --no-overwrite options.

pool-destroy pool-or-uuid

Destroy (stop) a given pool object. Libvirt will no longer manage the storage described by the pool object, but the raw data contained in the pool is not changed, and can be later recovered with pool-create.

pool-delete pool-or-uuid

Destroy the resources used by a given pool object. This operation is non-recoverable. The pool object will still exist after this command, ready for the creation of new storage volumes.

pool-dumpxml [--inactive] pool-or-uuid

Returns the

XML

information about the pool object. --inactive tells virsh to dump pool configuration that will be used on next start of the pool as opposed to the current pool configuration.

pool-edit pool-or-uuid

Edit the

XML

configuration file for a storage pool.

This is equivalent to:

 virsh pool-dumpxml pool > pool.xml
 vi pool.xml (or make changes with your other text editor)
 virsh pool-define pool.xml

except that it does some error checking.

The editor used can be supplied by the $VISUAL or $EDITOR environment variables, and defaults to "vi".

pool-info [--bytes] pool-or-uuid

Returns basic information about the pool object. If --bytes is specified the sizes of basic info are not converted to human friendly units.

pool-list [--inactive] [--all] [--persistent] [--transient] [--autostart] [--no-autostart] [[--details] [--uuid] [--name] [<type>]

List pool objects known to libvirt. By default, only active pools are listed; --inactive lists just the inactive pools, and --all lists all pools.

In addition, there are several sets of filtering flags. --persistent is to list the persistent pools, --transient is to list the transient pools. --autostart lists the autostarting pools, --no-autostart lists the pools with autostarting disabled. If --uuid is specified only pool's UUIDs are printed. If --name is specified only pool's names are printed. If both --name and --uuid are specified, pool's

UUID

and names are printed side by side without any header. Option --details is mutually exclusive with options --uuid and --name.

You may also want to list pools with specified types using type, the pool types must be separated by comma, e.g. --type dir,disk. The valid pool types include 'dir', 'fs', 'netfs', 'logical', 'disk', 'iscsi', 'scsi', 'mpath', 'rbd', 'sheepdog' and 'gluster'.

The --details option instructs virsh to additionally display pool persistence and capacity related information where available.

NOTE:

When talking to older servers, this command is forced to use a series of

API

calls with an inherent race, where a pool might not be listed or might appear more than once if it changed state between calls while the list was being collected. Newer servers do not have this problem.

pool-name uuid

Convert the uuid to a pool name.

pool-refresh pool-or-uuid

Refresh the list of volumes contained in pool.

pool-start pool-or-uuid [--build] [[--overwrite] | [--no-overwrite]]

Start the storage pool, which is previously defined but inactive.

[--build] [[--overwrite] | [--no-overwrite]] perform a pool-build prior to pool-start to ensure the pool environment is in an expected state rather than needing to run the build command prior to startup. The --overwrite and --no-overwrite flags follow the same rules as pool-build. If just --build is provided, then pool-build is called with no flags.

Note: A storage pool that relies on remote resources such as an ``iscsi'' or a (v)HBA backed ``scsi'' pool may need to be refreshed multiple times in order to have all the volumes detected (see pool-refresh). This is because the corresponding volume devices may not be present in the host's filesystem during the initial pool startup or the current refresh attempt. The number of refresh retries is dependent upon the network connection and the time the host takes to export the corresponding devices.

pool-undefine pool-or-uuid

Undefine the configuration for an inactive pool.

pool-uuid pool

Returns the

UUID

of the named pool.

pool-event {[pool] event [--loop] [--timeout seconds] [--timestamp] | --list}

Wait for a class of storage pool events to occur, and print appropriate details of events as they happen. The events can optionally be filtered by pool. Using --list as the only argument will provide a list of possible event values known by this client, although the connection might not allow registering for all these events.

By default, this command is one-shot, and returns success once an event occurs; you can send

SIGINT

(usually via "Ctrl-C") to quit immediately. If --timeout is specified, the command gives up waiting for events after seconds have elapsed. With --loop, the command prints all events until a timeout or interrupt key.

When --timestamp is used, a human-readable timestamp will be printed before the event.

VOLUME COMMANDS

vol-create pool-or-uuid

FILE

[--prealloc-metadata]

Create a volume from an

XML

<file>. pool-or-uuid is the name or

UUID

of the storage pool to create the volume in.

FILE

is the

XML

<file> with the volume definition. An easy way to create the

XML

<file> is to use the vol-dumpxml command to obtain the definition of a pre-existing volume. [--prealloc-metadata] preallocate metadata (for qcow2 images which don't support full allocation). This option creates a sparse image file with metadata, resulting in higher performance compared to images with no preallocation and only slightly higher initial disk space usage.

Example

 virsh vol-dumpxml --pool storagepool1 appvolume1 > newvolume.xml
 vi newvolume.xml (or make changes with your other text editor)
 virsh vol-create differentstoragepool newvolume.xml

vol-create-from pool-or-uuid

FILE

[--inputpool pool-or-uuid] vol-name-or-key-or-path [--prealloc-metadata] [--reflink]

Create a volume, using another volume as input. pool-or-uuid is the name or

UUID

of the storage pool to create the volume in.

FILE

is the

XML

<file> with the volume definition. --inputpool pool-or-uuid is the name or uuid of the storage pool the source volume is in. vol-name-or-key-or-path is the name or key or path of the source volume. [--prealloc-metadata] preallocate metadata (for qcow2 images which don't support full allocation). This option creates a sparse image file with metadata, resulting in higher performance compared to images with no preallocation and only slightly higher initial disk space usage. When --reflink is specified, perform a

COW

lightweight copy, where the data blocks are copied only when modified. If this is not possible, the copy fails.

vol-create-as pool-or-uuid name capacity [--allocation size] [--format string] [--backing-vol vol-name-or-key-or-path] [--backing-vol-format string] [--prealloc-metadata] [--print-xml]

Create a volume from a set of arguments unless --print-xml is specified, in which case just the

XML

of the volume object is printed out without any actual object creation. pool-or-uuid is the name or

UUID

of the storage pool to create the volume in. name is the name of the new volume. For a disk pool, this must match the partition name as determined from the pool's source device path and the next available partition. For example, a source device path of /dev/sdb and there are no partitions on the disk, then the name must be sdb1 with the next name being sdb2 and so on. capacity is the size of the volume to be created, as a scaled integer (see

NOTES

above), defaulting to bytes if there is no suffix. --allocation size is the initial size to be allocated in the volume, also as a scaled integer defaulting to bytes. --format string is used in file based storage pools to specify the volume file format to use; raw, bochs, qcow, qcow2, vmdk, qed. Use extended for disk storage pools in order to create an extended partition (other values are validity checked but not preserved when libvirtd is restarted or the pool is refreshed). --backing-vol vol-name-or-key-or-path is the source backing volume to be used if taking a snapshot of an existing volume. --backing-vol-format string is the format of the snapshot backing volume; raw, bochs, qcow, qcow2, qed, vmdk, host_device. These are, however, meant for file based storage pools. [--prealloc-metadata] preallocate metadata (for qcow2 images which don't support full allocation). This option creates a sparse image file with metadata, resulting in higher performance compared to images with no preallocation and only slightly higher initial disk space usage.

vol-clone [--pool pool-or-uuid] vol-name-or-key-or-path name [--prealloc-metadata] [--reflink]

Clone an existing volume within the parent pool. Less powerful, but easier to type, version of vol-create-from. --pool pool-or-uuid is the name or

UUID

of the storage pool that contains the source volume, and will contain the new volume. vol-name-or-key-or-path is the name or key or path of the source volume. name is the name of the new volume. [--prealloc-metadata] preallocate metadata (for qcow2 images which don't support full allocation). This option creates a sparse image file with metadata, resulting in higher performance compared to images with no preallocation and only slightly higher initial disk space usage. When --reflink is specified, perform a

COW

lightweight copy, where the data blocks are copied only when modified. If this is not possible, the copy fails.

vol-delete [--pool pool-or-uuid] vol-name-or-key-or-path [--delete-snapshots]

Delete a given volume. --pool pool-or-uuid is the name or

UUID

of the storage pool the volume is in. vol-name-or-key-or-path is the name or key or path of the volume to delete.

The --delete-snapshots flag specifies that any snapshots associated with the storage volume should be deleted as well. Not all storage drivers support this option, presently only rbd.

vol-upload [--pool pool-or-uuid] [--offset bytes] [--length bytes] [--sparse] vol-name-or-key-or-path local-file

Upload the contents of local-file to a storage volume. --pool pool-or-uuid is the name or

UUID

of the storage pool the volume is in. vol-name-or-key-or-path is the name or key or path of the volume where the file will be uploaded. If --sparse is specified, this command will preserve volume sparseness. --offset is the position in the storage volume at which to start writing the data. The value must be 0 or larger. --length is an upper bound of the amount of data to be uploaded. A negative value is interpreted as an unsigned long long value to essentially include everything from the offset to the end of the volume. An error will occur if the local-file is greater than the specified length. See the description for the libvirt virStorageVolUpload

API

for details regarding possible target volume and pool changes as a result of the pool refresh when the upload is attempted.

vol-download [--pool pool-or-uuid] [--offset bytes] [--length bytes] [--sparse] vol-name-or-key-or-path local-file

Download the contents of a storage volume to local-file. --pool pool-or-uuid is the name or

UUID

of the storage pool the volume is in. vol-name-or-key-or-path is the name or key or path of the volume to download. If --sparse is specified, this command will preserve volume sparseness. --offset is the position in the storage volume at which to start reading the data. The value must be 0 or larger. --length is an upper bound of the amount of data to be downloaded. A negative value is interpreted as an unsigned long long value to essentially include everything from the offset to the end of the volume.

vol-wipe [--pool pool-or-uuid] [--algorithm algorithm] vol-name-or-key-or-path

Wipe a volume, ensure data previously on the volume is not accessible to future reads. --pool pool-or-uuid is the name or

UUID

of the storage pool the volume is in. vol-name-or-key-or-path is the name or key or path of the volume to wipe. It is possible to choose different wiping algorithms instead of re-writing volume with zeroes. This can be done via --algorithm switch.

Supported algorithms
  zero       - 1-pass all zeroes
  nnsa       - 4-pass 

NNSA

 Policy Letter 

NAP-14.1-C

 (

XVI-8

) for
               sanitizing removable and non-removable hard disks:
               random x2, 0x00, verify.
  dod        - 4-pass DoD 5220.22-M section 8-306 procedure for
               sanitizing removable and non-removable rigid
               disks: random, 0x00, 0xff, verify.
  bsi        - 9-pass method recommended by the German Center of
               Security in Information Technologies
               (www.bsi.bund.de): 0xff, 0xfe, 0xfd, 0xfb,
               0xf7, 0xef, 0xdf, 0xbf, 0x7f.
  gutmann    - The canonical 35-pass sequence described in
               Gutmann's paper.
  schneier   - 7-pass method described by Bruce Schneier in
               ``Applied Cryptography'' (1996): 0x00, 0xff,
               random x5.
  pfitzner7  - Roy Pfitzner's 7-random-pass method: random x7.
  pfitzner33 - Roy Pfitzner's 33-random-pass method: random x33.
  random     - 1-pass pattern: random.
  trim       - 1-pass trimming the volume using 

TRIM

 or 

DISCARD

Note: The "scrub" binary will be used to handle the 'nnsa', 'dod', 'bsi', 'gutmann', 'schneier', 'pfitzner7' and 'pfitzner33' algorithms. The availability of the algorithms may be limited by the version of the "scrub" binary installed on the host. The 'zero' algorithm will write zeroes to the entire volume. For some volumes, such as sparse or rbd volumes, this may result in completely filling the volume with zeroes making it appear to be completely full. As an alternative, the 'trim' algorithm does not overwrite all the data in a volume, rather it expects the storage driver to be able to discard all bytes in a volume. It is up to the storage driver to handle how the discarding occurs. Not all storage drivers or volume types can support 'trim'.

vol-dumpxml [--pool pool-or-uuid] vol-name-or-key-or-path

Output the volume information as an

XML

dump to stdout. --pool pool-or-uuid is the name or

UUID

of the storage pool the volume is in. vol-name-or-key-or-path is the name or key or path of the volume to output the

XML

of.

vol-info [--pool pool-or-uuid] vol-name-or-key-or-path [--bytes] [--physical]

Returns basic information about the given storage volume. --pool pool-or-uuid is the name or

UUID

of the storage pool the volume is in. vol-name-or-key-or-path is the name or key or path of the volume to return information for. If --bytes is specified the sizes are not converted to human friendly units. If --physical is specified, then the host physical size is returned and displayed instead of the allocation value. The physical value for some file types, such as qcow2 may have a different (larger) physical value than is shown for allocation. Additionally sparse files will have different physical and allocation values.

vol-list [--pool pool-or-uuid] [--details]

Return the list of volumes in the given storage pool. --pool pool-or-uuid is the name or

UUID

of the storage pool. The --details option instructs virsh to additionally display volume type and capacity related information where available.

vol-pool [--uuid] vol-key-or-path

Return the pool name or

UUID

for a given volume. By default, the pool name is returned. If the --uuid option is given, the pool

UUID

is returned instead. vol-key-or-path is the key or path of the volume to return the pool information for.

vol-path [--pool pool-or-uuid] vol-name-or-key

Return the path for a given volume. --pool pool-or-uuid is the name or

UUID

of the storage pool the volume is in. vol-name-or-key is the name or key of the volume to return the path for.

vol-name vol-key-or-path

Return the name for a given volume. vol-key-or-path is the key or path of the volume to return the name for.

vol-key [--pool pool-or-uuid] vol-name-or-path

Return the volume key for a given volume. --pool pool-or-uuid is the name or

UUID

of the storage pool the volume is in. vol-name-or-path is the name or path of the volume to return the volume key for.

vol-resize vol-name-or-path capacity [--pool pool-or-uuid] [--allocate] [--delta] [--shrink]

Resize the capacity of the given volume, in bytes. --pool pool-or-uuid is the name or

UUID

of the storage pool the volume is in. vol-name-or-key-or-path is the name or key or path of the volume to resize. The new capacity might be sparse unless --allocate is specified. Normally, capacity is the new size, but if --delta is present, then it is added to the existing size. Attempts to shrink the volume will fail unless --shrink is present; capacity cannot be negative unless --shrink is provided, but a negative sign is not necessary. capacity is a scaled integer (see

NOTES

above), which defaults to bytes if there is no suffix. This command is only safe for storage volumes not in use by an active guest; see also blockresize for live resizing.

SECRET COMMANDS

The following commands manipulate ``secrets'' (e.g. passwords, passphrases and encryption keys). Libvirt can store secrets independently from their use, and other objects (e.g. volumes or domains) can refer to the secrets for encryption or possibly other uses. Secrets are identified using a See <libvirt.org/formatsecret.html> for documentation of the format used to represent properties of secrets.

secret-define file

Create a secret with the properties specified in file, with no associated secret value. If file does not specify a

UUID,

choose one automatically. If file specifies a

UUID

of an existing secret, replace its properties by properties defined in file, without affecting the secret value.

secret-dumpxml secret

Output properties of secret (specified by its

UUID

) as an

XML

dump to stdout.

secret-event {[secret] event [--loop] [--timeout seconds] [--timestamp] | --list}

Wait for a class of secret events to occur, and print appropriate details of events as they happen. The events can optionally be filtered by secret. Using --list as the only argument will provide a list of possible event values known by this client, although the connection might not allow registering for all these events.

By default, this command is one-shot, and returns success once an event occurs; you can send

SIGINT

(usually via "Ctrl-C") to quit immediately. If --timeout is specified, the command gives up waiting for events after seconds have elapsed. With --loop, the command prints all events until a timeout or interrupt key.

When --timestamp is used, a human-readable timestamp will be printed before the event.

secret-set-value secret base64

Set the value associated with secret (specified by its

UUID

) to the value Base64-encoded value base64.

secret-get-value secret

Output the value associated with secret (specified by its

UUID

) to stdout, encoded using Base64.

secret-undefine secret

Delete a secret (specified by its

UUID

), including the associated value, if any.

secret-list [--ephemeral] [--no-ephemeral] [--private] [--no-private]

Returns the list of secrets. You may also want to filter the returned secrets by --ephemeral to list the ephemeral ones, --no-ephemeral to list the non-ephemeral ones, --private to list the private ones, and --no-private to list the non-private ones.

SNAPSHOT COMMANDS

The following commands manipulate domain snapshots. Snapshots take the disk, memory, and device state of a domain at a point-of-time, and save it for future use. They have many uses, from saving a ``clean'' copy of an image to saving a domain's state before a potentially destructive operation. Snapshots are identified with a unique name. See <libvirt.org/formatsnapshot.html> for documentation of the format used to represent properties of snapshots.

snapshot-create domain [xmlfile] {[--redefine [--current]] | [--no-metadata] [--halt] [--disk-only] [--reuse-external] [--quiesce] [--atomic] [--live]}

Create a snapshot for domain domain with the properties specified in xmlfile. Normally, the only properties settable for a domain snapshot are the <name> and <description> elements, as well as <disks> if --disk-only is given; the rest of the fields are ignored, and automatically filled in by libvirt. If xmlfile is completely omitted, then libvirt will choose a value for all fields. The new snapshot will become current, as listed by snapshot-current.

If --halt is specified, the domain will be left in an inactive state after the snapshot is created.

If --disk-only is specified, the snapshot will only include disk state rather than the usual system checkpoint with vm state. Disk snapshots are faster than full system checkpoints, but reverting to a disk snapshot may require fsck or journal replays, since it is like the disk state at the point when the power cord is abruptly pulled; and mixing --halt and --disk-only loses any data that was not flushed to disk at the time.

If --redefine is specified, then all

XML

elements produced by snapshot-dumpxml are valid; this can be used to migrate snapshot hierarchy from one machine to another, to recreate hierarchy for the case of a transient domain that goes away and is later recreated with the same name and

UUID,

or to make slight alterations in the snapshot metadata (such as host-specific aspects of the domain

XML

embedded in the snapshot). When this flag is supplied, the xmlfile argument is mandatory, and the domain's current snapshot will not be altered unless the --current flag is also given.

If --no-metadata is specified, then the snapshot data is created, but any metadata is immediately discarded (that is, libvirt does not treat the snapshot as current, and cannot revert to the snapshot unless --redefine is later used to teach libvirt about the metadata again).

If --reuse-external is specified, and the snapshot

XML

requests an external snapshot with a destination of an existing file, then the destination must exist and be pre-created with correct format and metadata. The file is then reused; otherwise, a snapshot is refused to avoid losing contents of the existing files.

If --quiesce is specified, libvirt will try to use guest agent to freeze and unfreeze domain's mounted file systems. However, if domain has no guest agent, snapshot creation will fail. Currently, this requires --disk-only to be passed as well.

If --atomic is specified, libvirt will guarantee that the snapshot either succeeds, or fails with no changes; not all hypervisors support this. If this flag is not specified, then some hypervisors may fail after partially performing the action, and dumpxml must be used to see whether any partial changes occurred.

If --live is specified, libvirt takes the snapshot (checkpoint) while the guest is running. Both disk snapshot and domain memory snapshot are taken. This increases the size of the memory image of the external checkpoint. This is currently supported only for external checkpoints.

Existence of snapshot metadata will prevent attempts to undefine a persistent domain. However, for transient domains, snapshot metadata is silently lost when the domain quits running (whether by command such as destroy or by internal guest action).

snapshot-create-as domain {[--print-xml] | [--no-metadata] [--halt] [--reuse-external]} [name] [description] [--disk-only [--quiesce]] [--atomic] [[--live] [--memspec memspec]] [--diskspec] diskspec]...

Create a snapshot for domain domain with the given <name> and <description>; if either value is omitted, libvirt will choose a value. If --print-xml is specified, then

XML

appropriate for snapshot-create is output, rather than actually creating a snapshot. Otherwise, if --halt is specified, the domain will be left in an inactive state after the snapshot is created, and if --disk-only is specified, the snapshot will not include vm state.

The --memspec option can be used to control whether a checkpoint is internal or external. The --memspec flag is mandatory, followed by a memspec of the form [file=]name[,snapshot=type], where type can be no, internal, or external. To include a literal comma in file=name, escape it with a second comma. --memspec cannot be used together with --disk-only.

The --diskspec option can be used to control how --disk-only and external checkpoints create external files. This option can occur multiple times, according to the number of <disk> elements in the domain xml. Each <diskspec> is in the form disk[,snapshot=type][,driver=type][,file=name]. A diskspec must be provided for disks backed by block devices as libvirt doesn't auto-generate file names for those. To include a literal comma in disk or in file=name, escape it with a second comma. A literal --diskspec must precede each diskspec unless all three of domain, name, and description are also present. For example, a diskspec of ``vda,snapshot=external,file=/path/to,,new'' results in the following

XML:

  <disk name='vda' snapshot='external'>
    <source file='/path/to,new'/>
  </disk>

If --reuse-external is specified, and the domain

XML

or diskspec option requests an external snapshot with a destination of an existing file, then the destination must exist and be pre-created with correct format and metadata. The file is then reused; otherwise, a snapshot is refused to avoid losing contents of the existing files.

If --quiesce is specified, libvirt will try to use guest agent to freeze and unfreeze domain's mounted file systems. However, if domain has no guest agent, snapshot creation will fail. Currently, this requires --disk-only to be passed as well.

If --no-metadata is specified, then the snapshot data is created, but any metadata is immediately discarded (that is, libvirt does not treat the snapshot as current, and cannot revert to the snapshot unless snapshot-create is later used to teach libvirt about the metadata again). This flag is incompatible with --print-xml.

If --atomic is specified, libvirt will guarantee that the snapshot either succeeds, or fails with no changes; not all hypervisors support this. If this flag is not specified, then some hypervisors may fail after partially performing the action, and dumpxml must be used to see whether any partial changes occurred.

If --live is specified, libvirt takes the snapshot while the guest is running. This increases the size of the memory image of the external checkpoint. This is currently supported only for external checkpoints.

snapshot-current domain {[--name] | [--security-info] | [snapshotname]}

Without snapshotname, this will output the snapshot

XML

for the domain's current snapshot (if any). If --name is specified, just the current snapshot name instead of the full xml. Otherwise, using --security-info will also include security sensitive information in the

XML.

With snapshotname, this is a request to make the existing named snapshot become the current snapshot, without reverting the domain.

snapshot-edit domain [snapshotname] [--current] {[--rename] | [--clone]}

Edit the

XML

configuration file for snapshotname of a domain. If both snapshotname and --current are specified, also force the edited snapshot to become the current snapshot. If snapshotname is omitted, then --current must be supplied, to edit the current snapshot.

This is equivalent to:

 virsh snapshot-dumpxml dom name > snapshot.xml
 vi snapshot.xml (or make changes with your other text editor)
 virsh snapshot-create dom snapshot.xml --redefine [--current]

except that it does some error checking.

The editor used can be supplied by the $VISUAL or $EDITOR environment variables, and defaults to "vi".

If --rename is specified, then the edits can change the snapshot name. If --clone is specified, then changing the snapshot name will create a clone of the snapshot metadata. If neither is specified, then the edits must not change the snapshot name. Note that changing a snapshot name must be done with care, since the contents of some snapshots, such as internal snapshots within a single qcow2 file, are accessible only from the original name.

snapshot-info domain {snapshot | --current}

Output basic information about a named <snapshot>, or the current snapshot with --current.

snapshot-list domain [--metadata] [--no-metadata] [{--parent | --roots | [{--tree | --name}]}] [{[--from] snapshot | --current} [--descendants]] [--leaves] [--no-leaves] [--inactive] [--active] [--disk-only] [--internal] [--external]

List all of the available snapshots for the given domain, defaulting to show columns for the snapshot name, creation time, and domain state.

If --parent is specified, add a column to the output table giving the name of the parent of each snapshot. If --roots is specified, the list will be filtered to just snapshots that have no parents. If --tree is specified, the output will be in a tree format, listing just snapshot names. These three options are mutually exclusive. If --name is specified only the snapshot name is printed. This option is mutually exclusive with --tree.

If --from is provided, filter the list to snapshots which are children of the given snapshot; or if --current is provided, start at the current snapshot. When used in isolation or with --parent, the list is limited to direct children unless --descendants is also present. When used with --tree, the use of --descendants is implied. This option is not compatible with --roots. Note that the starting point of --from or --current is not included in the list unless the --tree option is also present.

If --leaves is specified, the list will be filtered to just snapshots that have no children. Likewise, if --no-leaves is specified, the list will be filtered to just snapshots with children. (Note that omitting both options does no filtering, while providing both options will either produce the same list or error out depending on whether the server recognizes the flags). Filtering options are not compatible with --tree.

If --metadata is specified, the list will be filtered to just snapshots that involve libvirt metadata, and thus would prevent undefine of a persistent domain, or be lost on destroy of a transient domain. Likewise, if --no-metadata is specified, the list will be filtered to just snapshots that exist without the need for libvirt metadata.

If --inactive is specified, the list will be filtered to snapshots that were taken when the domain was shut off. If --active is specified, the list will be filtered to snapshots that were taken when the domain was running, and where the snapshot includes the memory state to revert to that running state. If --disk-only is specified, the list will be filtered to snapshots that were taken when the domain was running, but where the snapshot includes only disk state.

If --internal is specified, the list will be filtered to snapshots that use internal storage of existing disk images. If --external is specified, the list will be filtered to snapshots that use external files for disk images or memory state.

snapshot-dumpxml domain snapshot [--security-info]

Output the snapshot

XML

for the domain's snapshot named snapshot. Using --security-info will also include security sensitive information. Use snapshot-current to easily access the

XML

of the current snapshot.

snapshot-parent domain {snapshot | --current}

Output the name of the parent snapshot, if any, for the given snapshot, or for the current snapshot with --current.

snapshot-revert domain {snapshot | --current} [{--running | --paused}] [--force]

Revert the given domain to the snapshot specified by snapshot, or to the current snapshot with --current. Be aware that this is a destructive action; any changes in the domain since the last snapshot was taken will be lost. Also note that the state of the domain after snapshot-revert is complete will be the state of the domain at the time the original snapshot was taken.

Normally, reverting to a snapshot leaves the domain in the state it was at the time the snapshot was created, except that a disk snapshot with no vm state leaves the domain in an inactive state. Passing either the --running or --paused flag will perform additional state changes (such as booting an inactive domain, or pausing a running domain). Since transient domains cannot be inactive, it is required to use one of these flags when reverting to a disk snapshot of a transient domain.

There are two cases where a snapshot revert involves extra risk, which requires the use of --force to proceed. One is the case of a snapshot that lacks full domain information for reverting configuration (such as snapshots created prior to libvirt 0.9.5); since libvirt cannot prove that the current configuration matches what was in use at the time of the snapshot, supplying --force assures libvirt that the snapshot is compatible with the current configuration (and if it is not, the domain will likely fail to run). The other is the case of reverting from a running domain to an active state where a new hypervisor has to be created rather than reusing the existing hypervisor, because it implies drawbacks such as breaking any existing

VNC

or Spice connections; this condition happens with an active snapshot that uses a provably incompatible configuration, as well as with an inactive snapshot that is combined with the --start or --pause flag.

snapshot-delete domain {snapshot | --current} [--metadata] [{--children | --children-only}]

Delete the snapshot for the domain named snapshot, or the current snapshot with --current. If this snapshot has child snapshots, changes from this snapshot will be merged into the children. If --children is passed, then delete this snapshot and any children of this snapshot. If --children-only is passed, then delete any children of this snapshot, but leave this snapshot intact. These two flags are mutually exclusive.

If --metadata is specified, then only delete the snapshot metadata maintained by libvirt, while leaving the snapshot contents intact for access by external tools; otherwise deleting a snapshot also removes the data contents from that point in time.

NWFILTER COMMANDS

The following commands manipulate network filters. Network filters allow filtering of the network traffic coming from and going to virtual machines. Individual network traffic filters are written in and may contain references to other network filters, describe traffic filtering rules, or contain both. Network filters are referenced by virtual machines from within their interface description. A network filter may be referenced by multiple virtual machines' interfaces.

nwfilter-define xmlfile

Make a new network filter known to libvirt. If a network filter with the same name already exists, it will be replaced with the new

XML.

Any running virtual machine referencing this network filter will have its network traffic rules adapted. If for any reason the network traffic filtering rules cannot be instantiated by any of the running virtual machines, then the new

XML

will be rejected.

nwfilter-undefine nwfilter-name

Delete a network filter. The deletion will fail if any running virtual machine is currently using this network filter.

nwfilter-list

List all of the available network filters.

nwfilter-dumpxml nwfilter-name

Output the network filter

XML.

nwfilter-edit nwfilter-name

Edit the

XML

of a network filter.

This is equivalent to:

 virsh nwfilter-dumpxml myfilter > myfilter.xml
 vi myfilter.xml (or make changes with your other text editor)
 virsh nwfilter-define myfilter.xml

except that it does some error checking. The new network filter may be rejected due to the same reason as mentioned in nwfilter-define.

The editor used can be supplied by the $VISUAL or $EDITOR environment variables, and defaults to "vi".

HYPERVISOR-SPECIFIC COMMANDS

Use of the following commands is strongly discouraged. They can cause libvirt to become confused and do the wrong thing on subsequent operations. Once you have used these commands, please do not report problems to the libvirt developers; the reports will be ignored. If you find that these commands are the only way to accomplish something, then it is better to request that the feature be added as a first-class citizen in the regular libvirt library.

qemu-attach pid

Attach an externally launched

QEMU

process to the libvirt

QEMU

driver. The

QEMU

process must have been created with a monitor connection using the

UNIX

driver. Ideally the process will also have had the '-name' argument specified.

     $ qemu-kvm -cdrom ~/demo.iso \
         -monitor unix:/tmp/demo,server,nowait \
         -name foo \
         -uuid cece4f9f-dff0-575d-0e8e-01fe380f12ea  &
     $ QEMUPID=$!
     $ virsh qemu-attach $QEMUPID

Not all functions of libvirt are expected to work reliably after attaching to an externally launched

QEMU

process. There may be issues with the guest

ABI

changing upon migration and device hotplug or hotunplug may not work. The attached environment should be considered primarily read-only.

qemu-monitor-command domain { [--hmp] | [--pretty] } command...

Send an arbitrary monitor command command to domain domain through the qemu monitor. The results of the command will be printed on stdout. If --hmp is passed, the command is considered to be a human monitor command and libvirt will automatically convert it into

QMP

if needed. In that case the result will also be converted back from

QMP.

If --pretty is given, and the monitor uses

QMP,

then the output will be pretty-printed. If more than one argument is provided for command, they are concatenated with a space in between before passing the single command to the monitor.

qemu-agent-command domain [--timeout seconds | --async | --block] command...

Send an arbitrary guest agent command command to domain domain through qemu agent. --timeout, --async and --block options are exclusive. --timeout requires timeout seconds seconds and it must be positive. When --aysnc is given, the command waits for timeout whether success or failed. And when --block is given, the command waits forever with blocking timeout.

qemu-monitor-event [domain] [--event event-name] [--loop] [--timeout seconds] [--pretty] [--regex] [--no-case] [--timestamp]

Wait for arbitrary

QEMU

monitor events to occur, and print out the details of events as they happen. The events can optionally be filtered by domain or event-name. The 'query-events'

QMP

command can be used via qemu-monitor-command to learn what events are supported. If --regex is used, event-name is a basic regular expression instead of a literal string. If --no-case is used, event-name will match case-insensitively.

By default, this command is one-shot, and returns success once an event occurs; you can send

SIGINT

(usually via "Ctrl-C") to quit immediately. If --timeout is specified, the command gives up waiting for events after seconds have elapsed. With --loop, the command prints all events until a timeout or interrupt key. If --pretty is specified, any

JSON

event details are pretty-printed for better legibility.

When --timestamp is used, a human-readable timestamp will be printed before the event, and the timing information provided by

QEMU

will be omitted.

lxc-enter-namespace domain [--noseclabel] --- /path/to/binary [arg1, [arg2, ...]]

Enter the namespace of domain and execute the command "/path/to/binary" passing the requested args. The binary path is relative to the container root filesystem, not the host root filesystem. The binary will inherit the environment variables / console visible to virsh. The command will be run with the same sVirt context and cgroups placement as processes within the container. This command only works when connected to the

LXC

hypervisor driver. This command succeeds only if "/path/to/binary" has 0 exit status.

By default the new process will run with the security label of the new parent container. Use the --noseclabel option to instead have the process keep the same security label as "virsh".

ENVIRONMENT

The following environment variables can be set to alter the behaviour of "virsh"

VIRSH_DEBUG=<0 to 4>

Turn on verbose debugging of virsh commands. Valid levels are

*

VIRSH_DEBUG=0

DEBUG

- Messages at

ALL

levels get logged

*

VIRSH_DEBUG=1

INFO

- Logs messages at levels

INFO, NOTICE, WARNING

and

ERROR

*

VIRSH_DEBUG=2

NOTICE

- Logs messages at levels

NOTICE, WARNING

and

ERROR

*

VIRSH_DEBUG=3

WARNING

- Logs messages at levels

WARNING

and

ERROR

*

VIRSH_DEBUG=4

ERROR

- Messages at only

ERROR

level gets logged.

VIRSH_LOG_FILE=LOGFILE

The file to log virsh debug messages.

VIRSH_DEFAULT_CONNECT_URI

The hypervisor to connect to by default. Set this to a

URI,

in the same format as accepted by the connect option. This environment variable is deprecated in favour of the global

LIBVIRT_DEFAULT_URI

variable which serves the same purpose.

LIBVIRT_DEFAULT_URI

The hypervisor to connect to by default. Set this to a

URI,

in the same format as accepted by the connect option. This overrides the default

URI

set in any client config file and prevents libvirt from probing for drivers.

VISUAL

The editor to use by the edit and related options.

EDITOR

The editor to use by the edit and related options, if "VISUAL" is not set.

VIRSH_HISTSIZE

The number of commands to remember in the command history. The default value is 500.

LIBVIRT_DEBUG=LEVEL

Turn on verbose debugging of all libvirt

API

calls. Valid levels are

*

LIBVIRT_DEBUG=1

Messages at level

DEBUG

or above

*

LIBVIRT_DEBUG=2

Messages at level

INFO

or above

*

LIBVIRT_DEBUG=3

Messages at level

WARNING

or above

*

LIBVIRT_DEBUG=4

Messages at level

ERROR

For further information about debugging options consult <libvirt.org/logging.html>

BUGS

Report any bugs discovered to the libvirt community via the mailing list <libvirt.org/contact.html> or bug tracker <libvirt.org/bugs.html>. Alternatively report bugs to your software distributor / vendor.

AUTHORS

  Please refer to the AUTHORS file distributed with libvirt.

  Based on the xm man page by:
  Sean Dague <sean at dague dot net>
  Daniel Stekloff <dsteklof at us dot ibm dot com>

COPYRIGHT

Copyright (C) 2005, 2007-2015 Red Hat, Inc., and the authors listed in the libvirt file.

LICENSE

virsh is distributed under the terms of the v2+. This is free software; see the source for copying conditions. There is warranty; not even for or

SEE ALSO

virt-install(1), virt-xml-validate(1), virt-top(1), virt-df(1), <www.libvirt.org>