How to Perform a Failback-Takeover on a System That Uses Sun StorageTek Availability Suite Replication

Use this procedure to restart an application on the original primary cluster, cluster-paris, and use the current data on the original primary cluster. Any updates that occurred on the secondary cluster, cluster-newyork, while it was acting as primary are discarded.

The failback procedures apply only to clusters in a partnership. You need to perform the following procedure only once per partnership.

Conditionally, you can resume using the data on the original primary, cluster-paris. You must not have replicated data from the new primary, cluster-newyork, to the original primary cluster, cluster-paris, at any point after the takeover operation on cluster-newyork.

Before You Begin

Before you begin the failback-takeover operation, the clusters have the following roles:

• If the original primary cluster, cluster-paris, has failed, confirm that the cluster is booted and that the Sun Cluster Geographic Edition infrastructure is enabled on the cluster. For more information about booting a cluster, see Booting a Cluster in Sun Cluster Geographic Edition System Administration Guide.

• The protection group on cluster-newyork has the primary role.

• The protection group on cluster-paris has either the primary role or secondary role, depending on whether the protection group could be reached during the takeover.

1. Resynchronize the original primary cluster, cluster-paris, with the original secondary cluster, cluster-newyork.

   cluster-paris forfeits its own configuration and replicates the cluster-newyork configuration locally.

   1. On cluster-paris, resynchronize the partnership.

      phys-paris-1# geops update partnershipname

      partnershipname

      Specifies the name of the partnership

      ---

      Note –

      You need to perform this step only once per partnership, even if you are performing a failback-takeover for multiple protection groups in the partnership.

      ---

      For more information about synchronizing partnerships, see Resynchronizing a Partnership in Sun Cluster Geographic Edition System Administration Guide.

   2. Determine whether the protection group on the original primary cluster, cluster-paris, is active.

      phys-paris-1# geoadm status

   3. If the protection group on the original primary cluster is active, stop it.

      phys-paris-1# geopg stop -e local protectiongroupname

   4. Verify that the protection group is stopped.

      phys-paris-1# geoadm status

   5. On cluster-paris, resynchronize each protection group.

      If the protection group has been activated, deactivate the protection group by using the geopg stop command. For more information about deactivating a protection group, see How to Deactivate a Sun StorageTek Availability Suite Protection Group.

      phys-paris-1# geopg update protectiongroupname

      protectiongroupname

      Specifies the name of the protection group

      For more information about synchronizing protection groups, see How to Resynchronize a Sun StorageTek Availability Suite Protection Group.

2. On cluster-paris, validate the configuration for each protection group.

   Ensure that the protection group is not in an error state. A protection group cannot be started when it is in an error state.

   phys-paris-1# geopg validate protectiongroupname

   protectiongroupname

   Specifies a unique name that identifies a single protection group

   For more information, see How to Validate a Sun StorageTek Availability Suite Protection Group.

3. On cluster-paris, activate each protection group in the secondary role without data replication.

   Because the protection group on cluster-paris has a role of secondary, the geopg start command does not restart the application on cluster-paris.

   phys-paris-1# geopg start -e local -n protectiongroupname

   -e local

   Specifies the scope of the command.

   By specifying a local scope, the command operates on the local cluster only.

   -n

   Prevents the start of data replication at protection group startup.

   ---

   Note –

   You must use the -n option.

   ---

   protectiongroupname

   Specifies the name of the protection group.

   For more information, see How to Activate a Sun StorageTek Availability Suite Protection Group.

   Replication from cluster-newyork to cluster-paris is not started because the -n option is used on cluster-paris.

4. On cluster-paris, initiate a takeover for each protection group.

   phys-paris-1# geopg takeover [-f] protectiongroupname

   -f

   Forces the command to perform the operation without your confirmation

   protectiongroupname

   Specifies the name of the protection group

   For more information about the geopg takeover command, see How to Force Immediate Takeover of Sun StorageTek Availability Suite Services by a Secondary Cluster.

   The protection group on cluster-paris now has the primary role, and the protection group on cluster-newyork has the secondary role.

5. On cluster-newyork, activate each protection group.

   Because the protection group on cluster-newyork has a role of secondary, the geopg start command does not restart the application on cluster-newyork.

   phys-newyork-1# geopg start -e local [-n] protectiongroupname

   -e local

   Specifies the scope of the command.

   By specifying a local scope, the command operates on the local cluster only.

   -n

   Prevents the start of data replication at protection group startup.

   If you omit this option, the data replication subsystem starts at the same time as the protection group.

   protectiongroupname

   Specifies the name of the protection group.

   For more information about the geopg start command, see How to Activate a Sun StorageTek Availability Suite Protection Group.

6. Start data replication.

   To start data replication, activate the protection group on the primary cluster, cluster-paris.

   phys-paris-1# geopg start -e local protectiongroupname

   For more information about the geopg start command, see How to Activate a Sun StorageTek Availability Suite Protection Group.

7. For each cluster, verify that the protection groups are set correctly and that the application resource group status and the data replication status are okay.

   1. Verify that the protection group is now primary on cluster-paris and secondary on cluster-newyork. Run the following command from one node on each cluster:

      # geoadm status

   2. Check the runtime status of the application resource group and data replication for each Sun StorageTek Availability Suite protection group. Run the following commands from one node on each cluster:

      # clresourcegroup status -v resourcegroupname # clresource status -v AVSdevicegroupname-rep-rs

      Refer to the Status and Status Message fields that are presented for the data replication device group you want to check. For more information about these fields, see Table 2–1.

      For more information about the runtime status of data replication, see Checking the Runtime Status of Sun StorageTek Availability Suite Data Replication.