VERITAS Volume Manager 3.5 Troubleshooting Guide (August 2002)

Chapter 1, Recovery from Hardware Failure

Reattaching Disks

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

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 thiscase, removethe volume, recreate it onhardware that

is functioning correctly, and restore the contents of the volume from a backup or

from a snapshot image.

Reattaching Disks

You can perform a reattach operation if a disk fails completely and hot-relocation is not

possible, or if VxVM is started with some disk drivers unloaded and unloadable (causing

disks to enter the failed state). If the underlying problem has been ﬁxed, you can use the

vxreattach command to reattach the disks without plexes being ﬂagged as STALE.

However, the reattach must occur before any volumes on the disk are started.

The vxreattach command is called as part of disk recovery from the vxdiskadm

menus and during the boot process. If possible, vxreattach reattaches the failed disk

media record to the disk with the same device name. Reattachment places a disk in the

same disk group as it was located in before and retains its original disk media name.

After reattachment takes place, recovery may not be necessary. Reattachment can fail if

the original (or another) cause for the disk failure still exists.

You can use the command vxreattach -c to check whether reattachment is possible,

without performing the operation. Instead, it displays the disk group and disk media

name where the disk can be reattached.

See the vxreattach(1M) manual page for more information on the vxreattach

command.