This error is essentially a safety mechanism. It prevents opatchauto from attempting a rolling patch when it might leave the cluster in an inconsistent or unrecoverable state. Common triggers include:
# opatchauto apply -oh /u01/app/19.0.0/grid -nonrolling Use code with caution. Copied to clipboard Expected Execution Flow opatchauto72030 execute in nonrolling mode high quality
/u01/app/grid/OPatch/opatchauto apply -nonrolling Use code with caution. Copied to clipboard This error is essentially a safety mechanism