Building Disaster Recovery Serviceguard Solutions Using Metrocluster with Continuous Access EVA A.05.01

Table 7 Replication Modes and Failover Scenarios (continued)
ResolutionDT_APPLICATION_STARTUP_POLICYReplication
Mode
Failover
Scenario
Log Copy is in progress.
Because the WAIT_TIME is
set to <xx> minutes, the
program will wait for
completion of the log copy.
….
The DR Group is in
merging state.
….
The WAIT_TIME has
expired.
Error - Failed to failover
and swap the role of the
device group. The package
is NOT allowed to start up.
N/ASynchronousRemote failover
when the DR
To forcefully start up
the package even
DR Group is not failed over
and the package is not
started.
DR Group fails over and the
package is started.
Enhanced
Asynchronous
Group is in
RUNDOWN
state and link is
down
though data currency
cannot be determined,
create a
The following log message
appears in the package log
:
“FORCEFLAG” file in
package directory and
restart the package.
Warning - Unable to get
remote DR group state
because the CA link is
down.
The role of the device
group on this site is
"destination".
The state of the replication
link is down and the state
of data may not be current.
Because the package
startup policy is
DATA_CURRENCY_PREFERRED,
the package is NOT
allowed to start up.
Complex workload failover/failback scenarios
This section elaborates on the failure scenarios that can occur when a complex workload is
configured using Site Aware Disaster Tolerant Architecture.
Site failover
The Site Controller package performs the failover for Complex Workloads.
The Site Controller package monitors the active complex-workload packages, according to the
configuration, to detect a failure and initiate a site failover. When the complex-workload packages
are configured using the critical_package attribute, the Site Controller package detects and
initiates a site failover even if one of the critical packages fail. In a configuration where all the
packages in the complex workload are configured with the managed_package attribute, the Site
Controller package detects a failure and initiates site failover based on the cumulative status of all
the configured managed packages.
56 Understanding failover/failback scenarios