Building Disaster Recovery Serviceguard Solutions Using Metrocluster with 3PAR Remote Copy for Linux B.01.00.00, July 2013

3 Understanding failover/failback scenarios
Failover/failback scenarios in a Metrocluster package
The section describes a couple of rolling disaster scenarios. In the first scenario, the link had gone
down previously and is now up. The data from primary volume group is being synced with remote
Remote Copy volume group. The package has failed in the primary site and is now trying to start
at the recovery site. In the second scenario, the link had gone down and the data at the remote
volume group is not current. The package has failed in the primary site and is now trying to start
at the recovery site. Table 2 lists both these scenarios and the impact of Metrocluster package
attributes in such situations.
Table 2 Replication modes and failover scenarios
ResolutionMetrocluster ActionMetrocluster ParametersReplication
Mode
Replication
State/Link
Status
N/AReturns an error and
does not start the
package
RESYNC_WAIT_TIMEOUT = 0Periodic/SynchronousSyncing/Up
Waits till the specified
time. If sync is complete
RESYNC_WAIT_TIMEOUT is
greater than 0
before the specified
time, the package
starts, otherwise
package fails to start.
Waits till the sync is
complete and then
starts the package.
RESYNC_WAIT_TIMEOUT is
set to no_timeout
If the FORCEFLAG is
present, the package is
started up.
Returns an error and
does not start the
package.
AUTO_NONCURDATA = 0Periodic/SynchronousStopped/Down
N/AStarts the package.AUTO_NONCURDATA = 1
N/AReturns an error and
does not start the
package.
RESYNC_WAIT_TIMEOUT = 0Periodic onlyStarted/Up
Waits till the specified
time. If sync is complete
RESYNC_WAIT_TIMEOUT is
greater than 0
before the specified
time, the package
starts, otherwise
package fails to start.
Waits till the sync is
complete and then
starts the package.
RESYNC_WAIT_TIMEOUT is
set to no_timeout
22 Understanding failover/failback scenarios