Downgrading Oracle Grid Infrastructure to 12c Release 2 (12.2) when Upgrade Fails

If upgrade of Oracle Grid Infrastructure fails before CVU post upgrade checks succeed, then you can run gridSetup.sh and downgrade Oracle Grid Infrastructure to the earlier release.

Run this procedure to downgrade Oracle Clusterware only when the upgrade fails before CVU post upgrade checks succeed.
  1. From the later release Grid home, run gridSetup.sh in silent mode, to downgrade Oracle Clusterware:
    $ /u01/app/18.0.0/grid/gridSetup.sh -silent –downgrade [–nodes] nodes_to_be_downgraded
    [-oldHome] previous_release_grid_home_to_downgrade_to 
    [–configmethod] root | sudo [–sudopath path_to_sudo_program]
    [-sudousername sudoer_name] 

    On Windows systems, run setup.exe instead of gridSetup.sh.

Note:

You can downgrade the cluster nodes in any sequence.