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Please find below details regarding FS_CLONE -
The fs_clone phase is a command (not related to adcfgclone.pl) that is used to synchronize the patch file system with the run file system. Normally, the fs_clone phase should only be run when mentioned as part of a specific documented procedure.
You may perform a procedure that as a final step instructs you to run fs_clone. You do not have to do this immediately: the key requirement is to run fs_clone before you start the next patching cycle. And if you are performing multiple procedures, each of which requires fs_clone to be run at the end, you only need to run it once before the start of the next patching cycle.
fs_clone - Recreates the patch edition file system as an exact copy of the run edition file system. This phase cannot be specified with any other phase. Use of fs_clone is normally not required. Situations that do require fs_clone are will explicitly document that requirement. If running this phase, ensure that your current working directory is not within the patch edition file system.
Also for me when I usually apply fs_clone.
- while applying any patch using apply_mode=hotpatch
- Before apply any big patches I will do fs_clone
The "fs_clone" command recreates the patch edition file system by making a full copy of the run edition file system.
This command is required when the patch edition file system cannot be automatically synchronized with the run edition file system by adop.
Run the fs_clone command if you have done any of the following actions:
•Applied middle-tier technology patches to the run edition
•Changed run edition files manually (outside of online patching)
•Aborted an online patching cycle