vnstat (1)
NAME
vnstat - a console-based network traffic monitor
SYNOPSIS
vnstat [ -Ddhlmqrstuvw? ] [ --cleartop ] [ --config file ] [ --create ] [ --days ] [ --delete ] [ --dbdir directory ] [ --debug ] [ --disable ] [ --enable ] [ --exportdb ] [ --help ] [ --hours ] [ --importdb file ] [ -i interface ] [ --iface interface ] [ --iflist ] [ --json mode ] [ --live mode ] [ --locale locale ] [ --longhelp ] [ --months ] [ --nick nickname ] [ --oneline ] [ --query ] [ --rateunit ] [ --rebuildtotal ] [ --reset ] [ -ru ] [ --savemerged ] [ --short ] [ --showconfig ] [ --style number ] [ --sync ] [ --testkernel ] [ --top10 ] [ -tr time ] [ --traffic time ] [ --update ] [ --version ] [ --weeks ] [ --xml mode ]
DESCRIPTION
vnStat is a console-based network traffic monitor. It keeps a log of hourly, daily and monthly network traffic for the selected interface(s). However, it isn't a packet sniffer. The traffic information is read from the proc(5) or sys filesystems depending on availability. That way vnStat can be used even without root permissions on most systems.
The implementation is divided into two commands. The purpose of the
vnstat
command is to provide an interface for querying the traffic information stored
in network interface specific databases where as the daemon
vnstatd(1)
is responsible for data retrieval and storage. Although the daemon process
is constantly running as a service, it is actually spending most of the
time sleeping between data updates.
OPTIONS
- --cleartop
-
Remove all top 10 entries.
- --config file
-
Use
file
as configuration file instead of using normal configuration file search
functionality.
- --create
-
Create database for interface specified with
-i
or
--iface
option.
- -d, --days
-
Show traffic statistics on a daily basis for the last 30 days.
- --dbdir directory
-
Use
directory
as database directory instead of using the directory specified in the configuration
file or the hardcoded default if no configuration file is available.
- -D, --debug
-
Show additional debug output.
- --delete
-
Delete the database for the interface specified with
-i
or
--iface
and stop monitoring it.
- --enable, --disable
-
Enable or disable updates for selected interface. Useful for
interfaces that aren't always available, like ppp0. If the interface
goes down it should be disabled in order to avoid errors. Add something
like
vnstat -r --disable -i ppp0
to the script that's executed when
the interface goes down and
vnstat --enable -i ppp0
to the up script. These two options aren't needed when the daemon is used.
- --exportdb
-
Instead of showing the database with a formatted output, this output will
dump the whole database in a plain text based architeture independent format.
The output can be imported back using the
--importdb
option and can be used for moving a database from one host to another. See the
--importdb
documentation below for an example. Using the output for scripting is possible but
the outputs of
--xml
and
--json
are likely to be more suitable. The dump uses ; as field delimeter.
active;1activity status
interface;eth0name for the interface
nick;inetnick (if given)
created;1023895272creation date in Unix time
updated;1065467100when the database was updated
totalrx;569605all time total received MiB
totaltx;2023708all time total transmitted MiB
currx;621673719latest rx value in /proc
curtx;981730184latest tx value in /proc
totalrxk;644total rx KiB counter
totaltxk;494total tx KiB counter
btime;1059414541system boot time in Unix time
Then follows 30 lines like the following
d;0;1078696800;559;7433;68;557;1
where d = days, 0 = day number in database (0 is today), 1077314401 date in Unix time, 559 = rx MiB, 7433 = tx MiB, 68 = rx KiB, 557 = tx KiB and 1 tells that vnStat has filled this value and it is in use.
m;0;1078092000;48649;139704;527;252;1(x12)
t;0;1078351200;5979;47155;362;525;1(x10)
h;0;1078699800;118265;516545(x24)
m = months, t = top 10 and h = hours, all other fields are in the same order as in days except hours that doesn't have a separate KiB value. For hours the forth and fifth fields have values in KiB.
- -h, --hours
-
Show traffic statistics on a hourly basis for the last 24 hours.
- --importdb file
-
Import a database from
file
which was previously exported using the
--exportdb
option. This can be used to transfer a database between different architectures and
hosts, as the database is architecture dependant and not compatible between
different architectures. First dump the database on one host, e.g. with
vnstat -i ppp0 --exportdb >ppp0db.txt
and then import the text file on a different host using
vnstat -i ppp0 --importdb ppp0db.txt
- -i, --iface interface
-
Select one specific
interface
and apply actions to only it. For queries, it is possible to merge the
information of two or more interfaces using the
interface1+interface2+...
syntax.
- --iflist
-
Show list of currently available interfaces.
- --json mode
-
Show database content for selected interface or all interfaces in json format. All
traffic values in the output are in KiB. An optional
mode
parameter can be used for limiting the output to only selected information.
Everything is shown by default. Setting
mode
to 'h' will output only hours, 'd' days, 'm' months and 't' the top 10.
- -l, --live mode
-
Display current transfer rate for the selected interface in real time
until interrupted. Statistics will be shown after interruption if the runtime
was more than 10 seconds. An optional
mode
parameter can be used to select between the displaying of packets per
second (mode 0) and transfer counters (mode 1) during execution.
--style
can also be used to affect the layout of the output.
- --locale locale
-
Use
locale
instead of using the locale setting specified in the configuration file or the system
default if no configuration file is available.
- --longhelp
-
Show complete options list.
- -m, --months
-
Show traffic statistics on a monthly basis for the last 12 months.
- --nick nickname
-
Set the selected interfaces
nickname
as an alias the will be displayed in queries. Usage of
-u
is required to save the change and the daemon may not be running during
the set operation.
- --oneline
-
Show traffic summary for selected interface using one line with a parseable
format. The output contains 15 fields with ; used as field delimeter. The 1st
field contains the version information of the output that will be changed
in future versions of vnStat if the field structure changes. The following
fields in order 2) interface name, 3) timestamp for today, 4) rx for today,
5) tx for today, 6) total for today, 7) average traffic rate for today,
8) timestamp for current month, 9) rx for current month, 10) tx for current
month, 11) total for current month, 12) average traffic rate for today,
13) all time total rx, 14) all time total tx, 15) all time total traffic.
- -q, --query
-
Force database query mode.
- -r, --reset
-
Reset the internal counters in the database for the selected
interface. Use this if the interface goes down and back up,
otherwise that interface will get some extra traffic to its database.
Not needed when the daemon is used.
- --rebuildtotal
-
Reset the total traffic counters and recount those using recorded months.
- -ru, --rateunit
-
Swap the configured rate unit. If rate has been configured to be shown in
bytes then rate will be shown in bits if this option is present. In the same
way, if rate has been configured to be shown in bits then rate will be shown
in bytes when this option is present. Alternatively 0 or 1 can be given as
parameter for this option in order to select between bytes (0) and bits
(1) regardless of the configuration file setting.
- --savemerged
-
Write the end result of a database merge to the file
mergeddb
that can then be used as a new database if renamed. Top 10 traffic days
isn't included in the merge and will start empty in the new database.
The merge interface syntax is documented in
-i, --iface
option.
- -s, --short
-
Use short output mode. This mode is also used if more than one
database is available.
- --style number
-
Modify the content and style of outputs. Set
number
to 0 for a more narrow output, 1 for enabling bar column, 2
for same as previous but with average traffic rate visible in summary
and weekly outputs and 3 for enabling average traffic rate in all
outputs where it is supported. 4 disables the use of terminal control
characters in
-l / --live
mode.
- --sync
-
Synchronize internal counters in the database with interface
counters for the selected interface. Use this if the system is
rebooted but interface counters aren't reseted. Such can occur
when suspend to ram/disk is used. Not needed when the daemon is used.
- --testkernel
-
Test if the kernel boot time information always stays the same like it should or
if it's shifting.
- -t, --top10
-
Show all time top 10 traffic days.
- -tr time
-
Calculate how much traffic goes through the selected interface during
the given
time
seconds. The
time
will be 5 seconds if a number parameter isn't specified.
- -u, --update
-
Update all enabled databases or only the one specified with
-i
parameter. Not supported when the daemon is running.
- -v, --version
-
Show current version.
- -w, --weeks
-
Show traffic for 7 days, current and previous week.
- --xml mode
-
Show database content for selected interface or all interfaces in xml format. All
traffic values in the output are in KiB. An optional
mode
parameter can be used for limiting the output to only selected information.
Everything is shown by default. Setting
mode
to 'h' will output only hours, 'd' days, 'm' months and 't' the top 10.
- -?, --help
-
Show a command option summary.
FILES
- /var/lib/vnstat/
-
This directory contains all databases the program uses. Files are
named according to the monitored interfaces. A backup copy of each
database is kept in a file starting with a . (dot character) and
otherwise named according to the original file.
- /etc/vnstat.conf
-
Config file that will be used unless
$HOME/.vnstatrc
exists. See
vnstat.conf(5)
for more information.
EXAMPLES
- vnstat
-
Display traffic summary for the default interface or multiple interfaces
when more than one is monitored.
- vnstat -i eth0+eth1+eth3
-
Display traffic summary for a merge of interfaces eth0, eth1 and eth3.
- vnstat -i eth2 --xml
-
Output all information about interface eth2 in xml format.
- vnstat --json
-
Output all information of all monitored interfaces in json format.
- vnstat -u -i eth0
-
Force a database update for interface eth0 or create the database if it doesn't
exist. This is usually the first command used after a fresh install if the
daemon isn't used.
- vnstat -u -i eth0 --nick local
-
Give interface eth0 the nickname "local". That information will be later
later visible as a label when eth0 is queried. The database will also be updated
when this command is executed or created if the database doesn't exist.
- vnstat -i eth2 --delete
-
Delete database of interface eth2 and stop monitoring it.
RESTRICTIONS
Updates needs to be executed at least as often as it is possible for the interface to generate enough traffic to overflow the kernel interface traffic counter. Otherwise, it is possible that some traffic won't be seen. This isn't an issue for 64-bit kernels but at least one update every hour is always required in order to provide proper input. With 32-bit kernels, the maximum time between two updates depends on how fast the interface can transfer 4 GiB. Calculated theoretical times are:
-
10 Mbit: 54 minutes 100 Mbit: 5 minutes 1000 Mbit: 30 seconds
However, for 1000 Mbit interfaces updating once every minute is usually a usable solution if faster updates can't be used.
Estimated traffic values are likely to be somewhat inaccurate if daily traffic is low because only the MiB counter is used to calculate the estimate.
Virtual and aliased interfaces cannot be monitored because the kernel doesn't provide traffic information for that type of interfaces. Such interfaces are usually named eth0:0, eth0:1, eth0:2 etc. where eth0 is the actual interface being aliased.
Using long date output formats may cause misalignment in shown columns if the
length of the date exceeds the fixed size allocation.
AUTHOR
Teemu Toivola <tst at iki dot fi>
SEE ALSO
vnstatd(1), vnstati(1), vnstat.conf(5), proc(5), ifconfig(8), units(7)