Veritas Volume Manager 5.0 Administrator's Guide (September 2006)

Chapter
12
Administering
hot-relocation
If a volume has a disk I/O failure (for example, the disk has an uncorrectable error),
Veritas Volume Manager (VxVM) can detach the plex involved in the failure. I/O stops on
that plex but continues on the remaining plexes of the volume.
If a disk fails completely, VxVM can detach the disk from its disk group. All plexes on the
disk are disabled. If there are any unmirrored volumes on a disk when it is detached, those
volumes are also disabled.
Note: Apparent disk failure may not be due to a fault in the physical disk media or the disk
controller, but may instead be caused by a fault in an intermediate or ancillary component
such as a cable, host bus adapter, or power supply.
The hot-relocation feature in VxVM automatically detects disk failures, and notifies the
system administrator and other nominated users of the failures by electronic mail.
Hot-relocation also attempts to use spare disks and free disk space to restore redundancy
and to preserve access to mirrored and RAID-5 volumes. For more information, see the
section, “How hot-relocation works” on page 370.
If hot-relocation is disabled or you miss the electronic mail, you can use the
vxprint
command or the graphical user interface to examine the status of the disks. You may also
see driver error messages on the console or in the system messages file.
Failed disks must be removed and replaced manually as described in “Removing and
replacing disks” on page 112.
For more information about recovering volumes and their data after hardware failure, see
the Veritas Volume Manager Troubleshooting Guide.