Sun Cluster Geographic Edition System Administration Guide

ProcedureHow to Perform a Failback-Takeover on a System That Uses Sun StorEdge Availability Suite 3.2.1 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.


Note –

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 failover-takeover operation, the clusters have the following roles:

Steps
  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.


      # geops update partnership-name
      
      partnership-name

      Specifies the name of the partnership


      Note –

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


      For more information about synchronizing partnerships, see Resynchronizing a Partnership.

    2. 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 StorEdge Availability Suite 3.2.1 Protection Group.


      # geopg update protection-group-name
      
      protection-group-name

      Specifies the name of the protection group

      For more information about synchronizing protection groups, see How to Resynchronize a Sun StorEdge Availability Suite 3.2.1 Protection Group.

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


    # geopg validate protection-group-name 
    
    protection-group-name

    Specifies a unique name that identifies a single protection group

    For more information, see How to Validate a Sun StorEdge Availability Suite 3.2.1 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.


    # geopg start -e local -n protection-group-name
    
    -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.


    protection-group-name

    Specifies the name of the protection group

    For more information, see How to Activate a Sun StorEdge Availability Suite 3.2.1 Protection Group.

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

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


    # geopg takeover  [-f] protection-group-name
    
    -f

    Forces the command to perform the operation without your confirmation

    protection-group-name

    Specifies the name of the protection group

    For more information about the geopg takeover command, see How to Force Immediate Takeover of Sun StorEdge Availability Suite 3.2.1 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.


    # geopg start -e local [-n] protection-group-name
    
    -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.

    protection-group-name

    Specifies the name of the protection group

    For more information about the geopg start command, see How to Activate a Sun StorEdge Availability Suite 3.2.1 Protection Group.

  6. Start data replication.

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


    # geopg start -e local protection-group-name
    

    For more information about the geopg start command, see How to Activate a Sun StorEdge Availability Suite 3.2.1 Protection Group.