Veritas Volume Manager 5.1 SP1 Administrator"s Guide (5900-1506, April 2011)

group is initially imported by Node A, but the administrator wants to access the
disk group from Node B if Node A crashes. Such a failover scenario can be used
to provide manual high availability to data, where the failure of one node does
not prevent access to data. Failover can be combined with a “high availability”
monitor to provide automatic high availability to data: when Node B detects that
Node A has crashed or shut down, Node B imports (fails over) the disk group to
provide access to the volumes.
Veritas Volume Manager can support failover, but it relies on the administrator
or on an external high-availability monitor to ensure that the first system is shut
down or unavailable before the disk group is imported to another system.
See “Moving disk groups between systems” on page 226.
See the vxdg(1M) manual page.
Corruption of disk group configuration
If vxdg import is used with -C (clears locks) and/or -f (forces import) to import
a disk group that is still in use from another host, disk group configuration
corruption is likely to occur. Volume content corruption is also likely if a file
system or database is started on the imported volumes before the other host
crashes or shuts down.
If this kind of corruption occurs, your configuration must typically be rebuilt from
scratch and all data be restored from a backup. There are typically numerous
configuration copies for each disk group, but corruption nearly always affects all
configuration copies, so redundancy does not help in this case.
As long as the configuration backup daemon, vxconfigbackupd, is running, VxVM
will backup configurations whenever the configuration is changed. By default,
backups are stored in /etc/vx/cbr/bk. You may also manually backup the
configuration using the vxconfigbackup utility. The configuration can be rebuilt
using the vxrestore utility.
See the vxconfigbackup, vxconfigbackupd, vxconfigrestore man pages.
Disk group configuration corruption usually shows up as missing or duplicate
records in the configuration databases. This can result in a variety of vxconfigd
error messages
VxVM vxconfigd ERROR
V-5-1-569 Disk group group,Disk disk:
Cannot auto-import group: reason
where the reason can describe errors such as:
Administering cluster functionality (CVM)
Multiple host failover configurations
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