Configure automated peer recovery for the transaction service

Configure automated peer recovery to enable cluster members to automatically complete outstanding work for a failed cluster member. After we have configured automated peer recovery, recovery processing occurs without any intervention on the part.

Make sure that you understand the infrastructure requirements for automatic peer recovery. For more information, see the topics about how to choose between automated and manual transaction peer recovery and Disable file locking.

Automated peer recovery processing is the default setting when high availability is enabled. Follow the steps in this topic to ensure that the system is configured correctly. If we configured manual peer recovery and want to return to automated peer recovery, you must reconfigure the system back to the default settings.

1. Verify that high availability is enabled, and that the location of the transaction recovery log is specified, as described in Configure transaction properties for peer recovery.

2. Remove any high availability (HA) policies with a policy type of Static. Such policies might exist if you previously configured the system for manual peer recovery.

   1. In the navigation pane of the console, click Servers > Core groups > Core group settings. All the members of a cluster are in a single core group, which by default is the DefaultCoreGroup core group. Click the core group containing your cluster. The Core groups configuration panel is displayed.

   2. Under Additional Properties, click Policies. The current set of policies is displayed.

   3. Select any policies with a Policy type of Static, and a Match criteria that includes type = WAS_TRANSACTIONS. Click Delete.

3. Check to see if the required One-of-N transaction HA policy already exists. This policy has a Policy type of One of N, and a Match criteria that includes type = WAS_TRANSACTIONS. If this policy already exists, we do not have to take any further action. If the policy does not already exist, use the following steps to create it.

   1. Click New to create a new policy.

   2. Select One of N policy and click Next.

   3. Provide a name for the policy. This value is a free-form text string used only as a label in the console, however to assist readability in the console, use a name that associates the policy with the required behavior, for example, Clustered TM policy.

   4. Enter a description, if required.

   5. Select the Failback check box to ensure that a failed server reclaims its recovery log when it restarts, and click OK.

   6. Set values for the Is alive timer, Quorum, and Preferred servers only options, if required. See the contextual help for more information.

   7. Under Additional Properties, click Match criteria to open an empty Match criteria panel.

   8. Click New to create a new match criterion.

   9. Enter type in the Name field and WAS_TRANSACTIONS in the Value field. Click OK.

   10. Save your changes to the master configuration, ensuring selected the Synchronize changes with Nodes check box.

   11. Stop and restart the cluster members for the changes to take effect.

Results

Automated transaction peer recovery is configured for all the servers in the cluster. If a server fails, another server in the cluster will complete any outstanding work for the failed server.

Subtopics

• Disable file locking
  If we use Network File System Version 3 (NFSv3) for storing transaction recovery logs, and to use automated peer recovery, first disable file locking.

Related concepts

Choose between automated and manual transaction peer recovery

Related information:

Core group collection