VERITAS Volume Manager 3.5 Troubleshooting Guide (September 2004)

Recovery from Hardware Failure
Recovering a Mirrored Volume
Chapter 1
15
Recovering a Mirrored Volume
A system crash or an I/O error can corrupt one or more plexes of a mirrored volume and
leave no plex CLEAN or ACTIVE. You can mark one of the plexes CLEAN and instruct the
system to use that plex as the source for reviving the others as follows:
Step 1. Place the desired plex in the CLEAN state using the following command:
# vxmend fix clean
plex
For example, to place the plex vol01-02 in the CLEAN state:
# vxmend fix clean vol01-02
Step 2. To recover the other plexes in a volume from the CLEAN plex, the volume must be
disabled, and the other plexes must be STALE. If necessary, make any other CLEAN or
ACTIVE plexes STALE by running the following command on each of these plexes in turn:
# vxmend fix stale
plex
Step 3. To enable the CLEAN plex and to recover the STALE plexes from it, use the following
command:
# vxvol start
volume
For example, to recover volume vol01:
# vxvol start vol01
For more information about the vxmend and vxvol command, see the vxmend (1M) and
vxvol (1M) manual pages.
NOTE Following severe hardware failure of several disks or other related subsystems
underlying all the mirrored plexes of a volume, it may be impossible to recover the
volume using vxmend. In this case, remove the volume, recreate it on hardware that is
functioning correctly, and restore the contents of the volume from a backup or from a
snapshot image.