10.5 HP StoreVirtual Storage User Guide (AX696-96269, March 2013)

Figure 57 Two-site failure scenarios that are correctly using a virtual manager
Scenario 1—Communication between the sites is lost
In this scenario, the sites are both operating independently. On the appropriate site, depending
upon your configuration, select one of the storage systems, and start the virtual manager on it.
That site then recovers quorum and operates as the primary site. When communication between
the sites is restored, the managers in both sites reestablish communication and ensure that the data
in both sites is resynchronized. When the data is resynchronized, stop the virtual manager to return
to the disaster-tolerant configuration.
Scenario 2—One site becomes unavailable
For example, in the two-site disaster recovery model, one of the sites becomes unavailable. On
the site that remains up, all managers must be running. Select one of the storage systems at that
site and start the virtual manager on it. That site then regains quorum and can continue to operate
until the other site recovers. When the other site recovers, the managers in both sites re-establish
communication and ensure that the data in both sites is resynchronized. When the data is
resynchronized, stop the virtual manager to return to the disaster-tolerant configuration.
NOTE: If the unavailable site is not recoverable, you can create a new site with new storage
systems and reconstruct the cluster. Contact HP Support for help with cluster recovery. You must
have the serial number of one of your storage systems when making a support call.
Adding a virtual manager
If a two-system management group is created without using a Failover Manager, a virtual manager
is added automatically to the group by the Management Group, Clusters, and Volumes Wizard
to ensure fault-tolerance. If you use the CLI to create a management group, a virtual manager is
not automatically added. An alarm displays that there are not enough managers to maintain
quorum.
132 Working with managers and quorum