Cluster maintenance mode lets you temporarily suspend the cluster heartbeat while hardware maintenance is being performed. This is useful if you want to reset or power down the LAN switch without bringing down cluster servers.
Enabling the cluster maintenance mode from one cluster node puts the entire cluster in maintenance mode.
Log in as the root user to a node in the cluster, then enter the following at a command prompt:
cluster maintenance on
If the master server in the cluster is up, disabling the cluster maintenance mode from one cluster node brings the entire cluster out of maintenance mode. If the master server in the cluster goes down while the cluster is in cluster maintenance mode, you must disable cluster maintenance mode on all remaining cluster nodes in order to bring the cluster out of maintenance mode.
Log in as the root user to a node in the cluster, then enter the following at a command prompt:
cluster maintenance off
An expiry time can be set to automatically turn off the cluster maintenance mode. The specified time can be in any format, which is supported by the Linux 'date' utility. The ‘expiry_time’ option is applicable only when all the cluster nodes are on OES 2018 SP3.
Log in as the root user to a node in the cluster, then enter the following at a command prompt:
cluster maintenance on '2021-04-04 12:34:51'
All the cluster nodes will be in the maintenance mode till April 4,2021; time - 12:34:51. The cluster will be out of maintenance mode automatically at the specified time.