Failing over nodes
Nodes are failed over either by a graceful failover or hard failover operation. Graceful failover is the default.
- Graceful failover
- Hard failover
Graceful failover safely fails over nodes from clusters by allowing all in-flight operations to complete before implementing the failover operation. Graceful failover is the default behavior for the couchbase-cli failover operation.
Hard failover immediately fails over nodes from clusters. To perform a hard failover, the --force option is used. Hard failover is typically used when the node is in a bad state. Auto-failover is a hard failover.
couchbase-cli failover --cluster=HOST:PORT --server-failover=HOST:PORT --user=ADMIN --password=PASSWORD
Example: Setting failover, readd, recovery, and rebalance operations
The following example shows a failover, readd, recovery and rebalance sequence operations, where as, a node in a cluster is gracefully failed over, the node is re-added to the cluster, a delta recovery is implemented for the node, and rebalance is performed on the cluster:
couchbase-cli failover -c 192.168.0.1:8091 \\ --server-failover=192.168.0.2 \\ -u Administrator -p password couchbase-cli server-readd -c 192.168.0.1:8091 \\ --server-add=192.168.0.2 \\ -u Administrator -p password couchbase-cli recovery -c 192.168.0.1:8091 \\ --server-recovery=192.168.0.2 \\ --recovery-type=delta \\ -u Administrator -p password couchbase-cli rebalance -c 192.168.0.1:8091 \\ -u Administrator -p password
Example: Failing over a node immediately
The following example shows a node failing over immediately, that is, a hard failover is implemented rather than a graceful failover.
couchbase-cli failover -c 192.168.0.1:8091 \\ --server-failover=192.168.0.2 \\ --force \\ -u Administrator -p password