Command "opatch lsinventory" or "opatch apply" reports the error

ISSUE: 

Command "opatch lsinventory" or "opatch apply" reports below error:

<<
OUI-67076:OracleHomeInventory was not able to create a lock file, probably due to a failed OPatch Session. The loaded inventory might not show correctly what you have in the Oracle Home.
>>

REASON:

1. A previous "opatch apply" session failed and so a lock still exists on the local inventory.
2. When Opatch is invoked, it creates patch_locked file in $ORACLE_HOME/.patch_storage during its execution.
3. Hence, on an attempt to re-apply the patch or find list of patch (with opatch lsinventory) the presence of patch_locked file does not allow further processing and throws error.
4. If the patch application is interrupted or cancelled, this file gets retained under /.patch_storage directory.

SOLUTION:

If above error is observed while applying patch(opatch apply) then follow below steps:

Step 1) Check if the file "patch_locked" is present in the directory $ORACLE_HOME/.patch_storage

Step 2) If present, rename, move or remove the patch_locked file from $ORACLE_HOME/.patch_storage.
cd $ORACLE_HOME/.patch_storage
$ rm -rf patch_locked 

Step 3) Re-apply the patch.

If above error is observed while checking for list of applied patches(opatch lsinventory) then follow below procedure:

Step 1) Take a backup of $ORACLE_HOME/.patch_storage

$ cd $ORACLE_HOME

$ cp -r .patch_storage .patch_storage_ORG

Step 2) Remove $ORACLE_HOME/.patch_storage/patch_locked
$ cd $ORACLE_HOME/.patch_storage/
$ rm -rf patch_locked

Step 3) Create $ORACLE_HOME/.patch_storage/patch_free
$ cd $ORACLE_HOME/.patch_storage/
$ touch patch_free  

Step 4) Verify that "opatch lsinventory" no longer reports the error.
export ORACLE_HOME=$ORACLE_HOME
export PATH=$ORACLE_HOME/OPatch:$PATH
$ opatch lsinventory