Building Disaster Recovery Serviceguard Solutions Using Metrocluster with 3PAR Remote Copy

5 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 Remote Copy 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 Remote Copy volume group is not current. The package has failed in the primary
site and is now trying to start at the recovery site. Table 4 lists both these scenarios and the impact
of Metrocluster package attributes in such situations.
Table 4 Replication modes and failover scenarios
ResolutionMetrocluster ActionMetrocluster
Parameters
Replication
Mode
Replication
State/Link
Status
Remote
RCVG
Role
Local
RCVG
Role
N/AReturns an error and
does not start the
package.
RESYNC_WAIT_TIMEOUT
= 0
Periodic/SynchronousSyncing/UpPrimary
Primary
Rev
Secondary
Secondary
Rev
Waits till the specified
time. If sync is
RESYNC_WAIT_TIMEOUT
is greater than 0
complete 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
Returns an error and
does not start the
package.
AUTO_NONCURDATA
= 0
Periodic/SynchronousStopped/DownPrimary
Primary
Rev
Secondary
Secondary
Rev
present, the
package is
started up.
N/AStarts the package.AUTO_NONCURDATA
= 1
N/AReturns an error and
does not start the
package.
RESYNC_WAIT_TIMEOUT
= 0
Periodic
only
Started/UpPrimary
Primary
Rev
Secondary
Secondary
Rev
Waits till the specified
time. If sync is
RESYNC_WAIT_TIMEOUT
is greater than 0
complete 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
Start the remote
copy using
Metrocluster fails to
start the package. It
RESYNC_WAIT_TIMEOUT
= 0
PeriodicStopped/UpPrimary
Primary
Rev
Secondary
Secondary
Rev
startrcopygroup
command or from
logs the following
error message in the
log file.
the Inform
Error: The Remote
Copy is not
Management
Console GUI.
Failover/failback scenarios in a Metrocluster package 43