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

To list the site tags for a disk group
◆
To list the site tags for a disk group, use the following command:
# vxdg -o tag=site listtag diskgroup
Failure and recovery scenarios
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 481.Disruption of network link
between sites.
See “Recovering from host failure” on page 482.Failure of hosts at a site.
See “Recovering from storage failure” on page 482.Failure of storage at a site.
See “Recovering from site failure” on page 483.Failure of both hosts and
storage at a site.
Recovering from a loss of site connectivity
Warning: To avoid a potential loss of data, it is recommended that you configure
Veritas Cluster Server to handle network split-brain.
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. If the parallel instances of an
application issue writes to volumes, an unrecoverable data loss may occur and
manual intervention is needed. To avoid data loss, it is recommended that you
configure the VCS fencing mechanism to handle network split-brain situations.
When connectivity between the sites is restored, a serial split-brain condition will
be detected between the sites. One site must be chosen as having the preferred
version of the data and the disk group configuration copies. The data from the
chosen site is resynchronized to the other site. If new writes are issued to volumes
after the network split, they are overwritten with the data from the chosen site.
The configuration copies at the other sites are updated from the copies at the
chosen site.
481Administering sites and remote mirrors
Failure and recovery scenarios