Each node of the cluster can be in one of three processing states:
A node always starts in the ACCEPTING state. If you need to perform maintenance on a node, or if you want the node to leave the cluster in a clean way for other reasons, the cluster administrator can issue the stop command:
> grbcluster --server=server1 --password=cluster stopIf jobs are currently running, the state will change to DRAINING until the jobs finish, at which point it will change to STOPPED. If no jobs are running, the state will change to STOPPED immediately. In the DRAINING or STOPPED states, new jobs are rejected on that node. However, the node is still a member of the cluster and all the other features, commands, and APIs are still active.
Once a node is in the STOPPED state, you can safely remove it from the cluster (to perform maintenance, shut it down, etc.). To return it to the cluster and resume job processing, run the start command:
> grbcluster --server=server1 --password=cluster start
The flag --server is used to target a specific node in the cluster. Adding the --all flag requests that the command (e.g., start or stop) be applied to all nodes in the cluster.
By using the start and stop with a cluster of Compute Servers, you can effectively scale your cluster up or down, depending on the current cluster workload.