The crsctl start rollingpatch command transitions Oracle Clusterware and Oracle ASM into rolling patch mode. In this mode, the software tolerates nodes having different patch levels.
This command queries the Oracle Clusterware rolling patch state and Oracle ASM cluster state. If either one is not in rolling patch mode, it will use the appropriate method to transition Oracle Clusterware or Oracle ASM to rolling patch mode.
If Oracle Clusterware and Oracle ASM are both in rolling patch mode when you run this command, then this command does nothing.
The rolling patch mode is not persistent. If all the nodes in a cluster are shut down and restarted, then the cluster transitions out of rolling patch mode when it is restarted. Similarly, if Oracle Clusterware is stopped and then restarted on all nodes in the cluster, then the rolling patch mode is lost.
This command does not transition Oracle ASM to rolling patch mode if issued within an Oracle ASM Client Cluster.