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

At the chosen site, 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.
See “Handling conflicting configuration copies” on page 243.
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.
Recovering from storage failure
If storage fails at a site, the plexes that are configured on that storage are detached
locally if a site-consistent volume still has other mirrors available at the site. The
hot-relocation feature of VxVM will attempt to recreate the failed plexes on other
available storage in the disk group. If no plexes of a site-consistent volume remain
in operation at a site, and hot-relocation cannot recreate the plexes at that site,
the site is detached. Because site connectivity has not been lost, applications
running on hosts at the site can still access data at the other sites.
When the storage comes back online, the vxattachd reattaches the site
automatically.
See “Automatic site reattachment” on page 483.
If the vxattachd is not running, use the following commands to reattach a site
and recover the disk group:
# vxdg -g diskgroup reattachsite sitename
# vxrecover -g diskgroup
For more information about recovering a disk group, refer to the Veritas Volume
Manager Troubleshooting Guide.
Administering sites and remote mirrors
Failure and recovery scenarios
482