Failback

Failback is a manual process that should be performed with careful planning. It may involve manually restarting the RCM (when an RCM is used), and manually reversing the replication direction of the Replication Server:

1. Ensure that the primary Adaptive Server is in its normal running state and accepting connections.

2. If there is a secondary Adaptive Server running, and the direction of the replication has been switched during the failover, restore the replication direction to its original state so that the primary Adaptive Server is properly updated with the latest transactions. See the Replication Server Administration Guide for instructions.

3. If you are using an RCM, restart it. When the RCM is started using the OpenSwitch RCM_AUTOSTART parameter, you may need to restart the OpenSwitch servers to restart the RCM. See “Configuring an RCM to start automatically from OpenSwitch” for details.

4. Log in to the mutually-aware OpenSwitch as an administrator, and execute the following commands. Perform this step on only one of the OpenSwitch servers (either the primary or the secondary); the commands are automatically propagated to the other companion OpenSwitch.

   rp_stop <POOL>, <secondary_ASE>, NULL, 0, 1
   rp_server_status <primary_ASE>, UP
   rp_switch <POOL>, <secondary_ASE>, NULL,
        <primary_ASE>, 0, 1
   rp_start <POOL>, <secondary_ASE> NULL
   

All future incoming clients are redirected back to the primary Adaptive Server.

Copyright © 2005. Sybase Inc. All rights reserved.

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