Recovering a node

Restart a node that is unavailable by performing a node recovery procedure.

1. Decommission the failed node:

   1. In the header of Dev Studio, click Configure Decisioning Infrastructure Services .

   2. Select the service with the failed node by clicking the corresponding tab.

   3. For the failed node, in the Execute list, select Decommission.

2. Fix the root cause of the failure.

   Replace failed hardware parts, or the entire node.

3. Recover the data:

   • If the data was previously owned by the failed node and is available on replica nodes, delete the Cassandra commit log and data folders.
   • If the data was previously owned by the failed node and is not available on any replica node, perform data recovery from a backup file.

4. Restart the node and add it back to the applicable service.

   For more information, see Enabling decision management services.

5. Run the nodetool repair operation.

6. Remove unused key ranges by running the nodetool cleanup operation on all decision management nodes.

• Enabling decision management services

  Decision management services comprise the technical foundation of decision management. Learn more about decision management services and how to enable them to fully benefit from next-best-action strategies and other decision management features in Pega Platform.

• Managing decision management nodes

  Manage the decision management nodes in your application by running certain actions for them, for example, repair or clean-up.

• Pega alerts for Cassandra

  Determine the causes of performance issues in your application and learn how to resolve them by analyzing Cassandra-related alert messages.

• Troubleshooting Cassandra

  Identify the root cause of degraded performance by completing corresponding monitoring activities. Learn about the most commonly encountered Cassandra issues and how to address them.