Recovering a node
Recovery is performed after a server node is failed over and before rebalance operations. Either Delta or Full recovery can be specified.
- Fail over the node using either the graceful or hard failover method. Graceful failover is recommended.
- After the node is failed over, specify whether to use delta or full recovery.
- Perform maintenance operations on the node.
- Rebalance the cluster. During the rebalance, the same server node is added back to the cluster using the specified recovery method.
To use delta recovery during failover, recovery, and rebalance operations:
- Navigate to Server Nodes .
- Click Failover .
- Select Graceful Failover .
When failover happens on a specific node, that node is marked as Failed Over: Pending Removal
- Click Delta Recovery . Alternatively, select Full Recovery .
With delta recovery mode, Couchbase detects (with the Database Change Protocol) which data files are up-to-date and which are out-of-date and then, during rebalance, the existing data files on the failed over server node are retained and the out-of-date files are updated. With full recovery mode, the data files are removed from the failed over server node and then, during rebalance, the node is populated with new data files (active and replica vBuckets).
- To view the status of the server node, click Pending Rebalance .
The server node shows a Pending delta recovery status if delta recovery was selected. If you cancel the recovery, you can re-select either delta or full recovery.
- Click Rebalance .
The rebalance operation must be performed to re-add the failed over server node to the cluster.