What Does opatch apply Do in a Four-Node RAC Cluster?
Examine this command executed on the first node of a four-node cluster: $ < DATABASE_ORACLE_HOME >/OPatch/opatch apply 33575673 What does this command do?
Community Votes
60% of anonymous learners picked answer A. Votes are pick records left by other test-takers — they are not the verified answer.
Community Insight
This question tests whether you know OPatch's default cluster-aware behavior in a RAC database home, and the trap is assuming that omitting -all_nodes means a local-only patch.
OPatch apply in a RAC database home is cluster-aware: running it on the first node patches the specified Oracle Home on all cluster nodes. This guide establishes why option B is correct and why local-only interpretations miss OPatch's default RAC behavior.
Many candidates choose A (local-only) because the command lacks -all_nodes, but OPatch in RAC mode defaults to applying the patch to all nodes from the first node.
Community Discussion (6 comments)
Comments & Corrections
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Expert Analysis
Why the Answer Is Correct
The command specifies a database Oracle Home and runs OPatch apply without -local. In a RAC environment, OPatch is cluster-aware: when executed from the first node, it applies the patch to that Oracle Home on all cluster nodes. This matches option B. The "first node" detail matters because OPatch uses the cluster inventory to propagate the patch to every node. Option E is wrong because OPatch targets only the Oracle Home from which it is invoked, not every home of the same release.
Why the Other Options Are Wrong
Option A describes local-only patching, which would require -local (or a non-cluster-aware invocation). Option C and D claim all database Oracle Homes with the same release are patched, but OPatch does not sweep other homes. Option E combines the same-release error with all-node scope. The community comment from Tunglinfo9 reasons that "does not include options for multi-node patching" so it must be local, but that overlooks OPatch's default cluster-aware mode. As 217972f noted, Oracle's patching algorithm defaults to "patching mechanism = All-Node" when no rolling or minimize-downtime option applies.
Community Comment Notes
jackhsu0704 highlighted the -oh option, but the command uses the environment/path, not -oh. lcoleandro pointed to "Cluster-aware Execution (RAC Mode)" and the default behavior of applying to all nodes. The vote split (A:60, B:40) shows this is a common trap; the source key's A reflects the local-only assumption. Oracle documentation and the All-Node default support B. Test_1 simply asserted A without addressing cluster awareness.
Exam Strategy
When an OPatch command in a RAC question lacks -local, default to the cluster-aware answer: one Oracle Home patched on all nodes. Remember that -all_nodes is not required for the default All-Node behavior, and -local is what restricts patching to the current node.
Frequently Asked Questions
Why does OPatch apply patch all nodes when -all_nodes is not specified?
In RAC, OPatch is cluster-aware and defaults to All-Node patching when no rolling or minimize-downtime option is provided.
Does OPatch apply patch all Oracle Homes of the same release in the cluster?
No; it patches only the Oracle Home from which the command is run, not every home of the same release.