Multinode adop patching:

 In a multi-node setup on EBS 12.2, we can apply patches individually on each node as well.

If ssh is enabled from primary to secondary node then it is not necessary.

But I will show in this post how we can do it manually. This is an interview question and may be required sometimes.

Scenario 1: Shared Application Tier File System with SSH enabled

primary node run below

adop phase=<phase_name>

Scenario 2: Shared Application Tier File System without SSH enabled

primary node: 

adop phase=<phase_name> allnodes=no action=db

secondary node:

adop phase=<phase_name> allnodes=no action=nodb

Note: In a multi-node environment, the cleanup phase is to be executed on the primary node only as it is the DB phase. All other phases have to be executed on primary and all secondary nodes.

Scenario 3: Non-Shared Application Tier File System with SSH enabled

primary node run below

adop phase=<phase_name>

Scenario 4: Non-Shared Application Tier File System without SSH enabled

primary node: 

adop phase=<phase_name> allnodes=no action=db

secondary node:

adop phase=<phase_name> allnodes=no action=nodb