10.4. Upgrading OS Software in an Active Cluster

When you upgrade your OS software in an active cluster, you perform the upgrade on one node at a time.

If the OS software upgrade does not require reboot or does not impact the FailSafe software, there is no need to use the OS upgrade procedure. If you do not know whether the upgrade will impact FailSafe software or if the OS upgrade requires a machine reboot, follow the upgrade procedure described below.

The following procedure upgrades the OS software on node web-node3.

1. If resource groups are online on the node, use a cluster_mgr command to move them another node in the cluster. To move the resource group to another node in the cluster, there should be another node available in the failover policy domain of the resource group.

   The following cluster_mgr command moves resource group web-rg to another node in the cluster web-cluster:

   cmgr> admin move resource_group web-rg in cluster web-cluster

2. To stop HA services on the node web-node3, use the following cluster_mgr command. This command will move all the resource groups online on this node to other nodes in the cluster if possible.

   cmgr> stop ha_services on node web-node3 for cluster web-cluster

   If it is not possible to move resource groups that are online on node web-node3, the above command will fail. You can use the force option to stop HA services in a node even in the case of an error.

3. Perform the OS upgrade in the node web-node3.

4. After the OS upgrade, make sure cluster processes (cmond, cad, crsd) are running.

5. Restart HA services on the node. The following cluster_mgr command restarts HA services on the node:

   cmgr> start ha_services on node web-node3 for cluster web-cluster

   Make sure the resource groups are running on the most appropriate node after restarting HA services.