hv_ata_pci_disengage (4)

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$FreeBSD: releng/11.0/share/man/man4/hv_ata_pci_disengage.4 276259 2014-12-26 22:30:18Z bapt $

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(The comments found at the beginning of the groff file "man4/hv_ata_pci_disengage.4freebsd".)

NAME

hv_ata_pci_disengage - Hyper-V ATA PCI Disengage driver

SYNOPSIS

To compile this driver into the kernel, place the following lines in the system kernel configuration file:

device hyperv

DESCRIPTION

The ifconfig driver prevents the native Fx ATA driver from loading in the presence of Hyper-V. Fx guests running on Hyper-V can take advantage of the Hyper-V Storage Virtual Consumer (hv_storvsc4 ) for using their IDE devices. Since the ATA driver serves IDE devices as well, there is a chance that the ATA driver may interfere with the operations of hv_storvsc4. The ifconfig driver avoids conflicts between the ATA driver and hv_storvsc4 by disabling the ATA driver when the Fx guest is booting.

A side effect of disabling the ATA driver is that CDROM may become inoperational on Fx guest partitions. If CDROM access is a must then users may use "set hw.ata.disk_enable=1" at boot time to prevent the ATA driver from being disabled.

SEE ALSO

hv_vmbus4, hv_utils4, hv_netvsc4, hv_storvsc4

HISTORY

Support for ifconfig first appeared in Fx 10.0 . The driver was developed through a joint effort between Citrix Incorporated, Microsoft Corporation, and Network Appliance Incorporated.

AUTHORS

An -nosplit Fx support for ifconfig was first added by An Microsoft BSD Integration Services Team Aq bsdic@microsoft.com .