Opatch Failed With Error Code 21 -

cd $ORACLE_HOME/bin fuser <filename> Example: fuser oracle This command will output the Process IDs (PIDs) that are currently accessing that file.

Navigate to this directory and look for the most recent log file (usually timestamped opatchYYYY-MM-DD_HH-MM-SSAM.log ). Open it and search for the keyword or "fuser" . opatch failed with error code 21

This error is notorious in the Oracle community. It is a non-specific "catch-all" error code that essentially means OPatch failed to apply the patch, but it doesn't immediately tell you why . However, through years of community troubleshooting and Oracle support documentation, we have identified the primary culprits behind this failure. This error is notorious in the Oracle community

You can ask OPatch to check if the patch is applicable and if files are busy before actually applying it. While this doesn't fix the error post-facto, it is excellent for prevention. You can ask OPatch to check if the