Error Code 21 - Opatch Failed With

ls -la /u01/app/oraInventory/locks/* If lock files exist and no other OPatch process is running, remove them:

opatch apply -debug The debug output will show every command OPatch tries to execute, making it easier to spot failures like missing make or file copy errors. If the error occurs during the relinking phase, try relinking manually before reapplying the patch: opatch failed with error code 21

Upgraded OPatch to version 13.9.4.2.0. The patch applied successfully. Case Study 2: /tmp Full of Old JAR Extractions Scenario: A middleware admin repeatedly failed with error code 21 on a WebLogic patch. Logs showed "No space left on device" even though df -h /tmp showed 30% free. ls -la /u01/app/oraInventory/locks/* If lock files exist and