Veritas Volume Manager 5.0.1 Administrator's Guide, HP-UX 11i v3, First Edition, November 2009

Failure scenarios and recovery procedures
Table 14-2 lists the possible failure scenarios and recovery procedures for the
Remote Mirror feature.
Table 14-2
Failure scenarios and recovery procedures
Recovery procedureFailure scenario
See “Recovering from a loss of site connectivity” on page 502.Disruption of network link
between sites.
See “Recovering from host failure” on page 502.Failure of hosts at a site.
See “Recovering from storage failure” on page 503.Failure of storage at a site.
See “Recovering from site failure” on page 503.Failure of both hosts and
storage at a site.
Recovering from a loss of site connectivity
If the network links between the sites are disrupted, the application environments
may continue to run in parallel, and this may lead to inconsistencies between the
disk group configuration copies at the sites. When connectivity between the sites
is restored, a serial split-brain condition may then exist between the sites. One
site must be chosen as having the preferred version of the disk group configuration
copies. The configuration copies at the other sites can then be updated from these
copies.
Use the following commands to reattach a site and recover the disk group:
# vxdg -g diskgroup -o overridessb reattachsite sitename
# vxrecover -g diskgroup
In the case that the host systems are configured at a single site with only storage
at the remote sites, the usual resynchronization mechanism of VxVM is used to
recover the remote plexes when the storage comes back on line.
Recovering from host failure
If one or more cluster nodes fail at a site, but the storage remains online, this is
handled either by VCS failover in the case of the Storage Foundation HA product,
or by node takeover in the case that the node was the master for a shared disk
group as supported by the Storage Foundation Cluster File System software.
Administering sites and remote mirrors
Failure scenarios and recovery procedures
502