Disaster recovery rehearsal in Continentalclusters

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Strengths
This section lists the strengths of the DR rehearsals feature.
1. Minimal application reconfiguration for rehearsal: Because the rehearsal package is configured to
use the volume group/filesystem that is used for the recovery package, the existing application
setup at the recovery cluster can be started for rehearsal with minimal reconfiguration. The only
reconfiguration would be application setup changes related to the use of a different client access
IP address, which is recommended during rehearsal.
2. Effective Rehearsal: The rehearsal package is configured with volume group/filesystem setup for
an actual recovery and allows the same application to be bundled for rehearsal. Hence the
rehearsal package is identical to the recovery package and therefore can be effectively used in
place of the recovery package to verify the environment without actually performing recovery.
3. No changes to the recovery package configuration: By using not using the recovery package, all
package configurations related changes required for rehearsal are isolated to the rehearsal
package, which is a separate package. This avoids the complexity and potential errors involved if
the recovery package was used for rehearsal (which requires changing of recovery package
configuration before rehearsal, and restoring the original configuration at the end of rehearsal).
4. Mutual exclusion between rehearsal and recovery: Because the rehearsal package is configured
with the recovery package’s volume group and filesystem directory names, allowing both
rehearsal and recovery attempts can result in resource collisions and impact data integrity. The
maintenance mode feature implemented in Continentalclusters prevents any attempt to perform
rehearsal and recovery at the same time.