Actions Performed by the Geographic Edition Software During a Takeover

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When you run the geopg takeover command, the software confirms that databases in the Oracle Data Guard Broker configuration on the standby cluster, that is, the future primary, are enabled (as you cannot perform a takeover to a disabled database). The software also confirms that the Oracle Data Guard command-line interface show configuration command shows one of the following states:

A SUCCESS state
Busy performing a health check (ORA-16610)
The remote database is unreachable (ORA-16625)
The show configuration command times out

If the show configuration command returns any other Oracle error code, the takeover fails.

If the original primary cluster, cluster-paris, can be reached, the software takes offline the application resource groups in the protection group and places them in an Unmanaged state.

On the original standby cluster, cluster-newyork, the software performs the following operations:

Runs the Oracle Data Guard command-line interface failover to standby-database-name command. If this command fails and the system remains a standby, the failover to standby-database-name immediate command is run.
Runs the script that is specified by the RoleChange_ActionCmd property.
If the protection group was active on the original standby cluster before the takeover, brings online all shadow Oracle database-server resource groups and application resource groups in the protection group. For HA for Oracle configurations, the dataguard_role resource property is also updated to reflect the new primary and standby clusters.

If the command completes successfully, the standby cluster, cluster-newyork, becomes the new primary cluster for the protection group. Databases that are associated with the Oracle Data Guard Broker configurations of the protection group have their role reversed according to the role of the protection group on the local cluster. The shadow Oracle database-server resource group and any other application resource group in the protection group are online on the new primary cluster. If the original primary cluster can be reached, it becomes the new standby cluster of the protection group. Replication of all databases that are associated with the Oracle Data Guard Broker configurations of the protection group are stopped.

Caution - After a successful takeover, data replication is stopped. If you want to continue to suspend replication, specify the –n option when you use the geopg start command. This option prevents the start of data replication from the new primary cluster to the new standby cluster.

If a previous operation fails, this command returns an error. Use the geoadm status command to view the status of each component. For example, the Configuration status of the protection group might be set to an Error state, depending on the cause of the failure. The protection group might be activated or deactivated.

If the Configuration status of the protection group is set to the Error state, revalidate the protection group by using the procedures that are described in How to Validate an Oracle Data Guard Protection Group.

If the configuration of the protection group is not the same on each partner cluster, you need to resynchronize the configuration by using the procedures described in How to Resynchronize a Protection Group in Oracle Solaris Cluster Geographic Edition System Administration Guide .