Migrating Services That Use Sun StorageTek Availability Suite With a Switchover

You perform a switchover of a Sun StorageTek Availability Suite protection group when you want to migrate services to the partner cluster in an orderly fashion. A switchover consists of the following:

• Application services are unmanaged on the former primary cluster, cluster-paris.

  For a reminder of which cluster is cluster-paris, see Example Sun Cluster Geographic Edition Cluster Configuration in Sun Cluster Geographic Edition System Administration Guide.

• The data replication role is reversed and now continues to run from the new primary, cluster-newyork, to the former primary, cluster-paris.

• Application services are brought online on the new primary cluster, cluster-newyork.

This section provides the following information:

• How to Switch Over a Sun StorageTek Availability Suite Protection Group From Primary to Secondary

• Actions Performed by the Sun Cluster Geographic Edition Software During a Switchover

How to Switch Over a Sun StorageTek Availability Suite Protection Group From Primary to Secondary

Before You Begin

For a switchover to occur, data replication must be active between the primary cluster and the secondary cluster. Additionally, the data volumes on the two clusters must be in a synchronized state.

Before you switch over a protection group from the primary cluster to the secondary cluster, ensure that the following conditions are met:

• Sun Cluster Geographic Edition software is running on the both clusters.

• The secondary cluster is a member of a partnership.

• Both cluster partners can be reached.

• The overall state of the protection group is OK.

1. Log in to a cluster node.

   You must be assigned the Geo Management RBAC rights profile to complete this procedure. For more information about RBAC, see Sun Cluster Geographic Edition Software and RBAC in Sun Cluster Geographic Edition System Administration Guide.

2. Initiate the switchover.

   The application resource groups that are a part of the protection group are stopped and started during the switchover.

   # geopg switchover [-f] -m newprimarycluster protectiongroupname

   -f

   Forces the command to perform the operation without asking you for confirmation

   -m newprimarycluster

   Specifies the name of the cluster that is to be the primary cluster for the protection group

   protectiongroupname

   Specifies the name of the protection group

Example 3–1 Forcing a Switchover From Primary to Secondary

This example performs a switchover to the secondary cluster.

# geopg switchover -f -m cluster-newyork avspg

Actions Performed by the Sun Cluster Geographic Edition Software During a Switchover

When you run the geopg switchover command, the software confirms that the volume sets that are associated with the device groups are in the replicating state. Then, the software performs the following actions on the original primary cluster:

• Removes affinities and resource dependencies between all the application resource groups in the protection group and the internal resource group, such as the lightweight resource groups

• Takes the application resource groups offline and places them in the Unmanaged state

• Waits for writes to complete

• Unmounts the primary volumes that correspond to the device groups in the protection group

• Stops data replication by placing all volume sets in logging mode

• Reverses the role of all volume sets

On the original secondary cluster, the command takes the following actions:

• Places all volume sets in logging mode

• Reverses the role of all volume sets

• Starts data replication by issuing update synchronization with the autosynchronization feature active

• Runs the script that is defined in the RoleChange_ActionCmd property

• Brings all application resource groups online and adds the affinities between the application resource groups and the internal resource groups, such as the lightweight resource group

If the command completes successfully, the secondary cluster, cluster-newyork, becomes the new primary cluster for the protection group. The original primary cluster, cluster-paris, becomes the new secondary cluster. Volume sets associated with a device group of the protection group have their role reversed according to the role of the protection group on the local cluster. The application resource group is online on the new primary cluster. Data replication from the new primary cluster to the new secondary cluster begins.

This command returns an error if any of the previous operations fails. Run the geoadm status command to view the status of each component. For example, the Configuration status of the protection group might be set to Error, 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 Error, revalidate the protection group by using the procedures described in How to Validate a Sun StorageTek Availability Suite 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 Sun StorageTek Availability Suite Protection Group.