Deeper understanding of POSIX / xattrs handling

[frankferrari]

Hey there!

I trying to wrap my head around the POSIX driver and the metadata concept as a file based approach that Opencloud is based on, but I struggle to find the all answering information out there. Maybe one can help me bring some light into this topic, regarding file transfers or backup handling etc.

1. As recommend I chose to create snapshot backups of my storage (using rsnapshot). Is it required/recommended to include the --xattrs flag to preseve the metadata? this would "bake" the metadata into the backup, making it "contaminated" if I copy it elsewhere than OC later.
   What happens if I dont? Would a rsync -a back from the backup lead to a new assimilation of the files by opencloud?

2. What If I would just partially restore directories from the backup? Would this miss out crucial data that is required for consistency? (.oc-nodes .oc-tmp or other ?) In other words, how should restoring backups look like?

3. How does the assimilation work? does it check if there is any metadata present? And would deleting the metadata (e.g. with getfattr) initiate a fresh assimilation.

4. Renaming data in the storage (even if docker is down) breaks the system, right? as the name is baked into the metadata, right?

These questions might all be somehow connected..

PS: This all came up after I had to manipulate storage data directly (even though it not encourage to do so). I needed to zip large projects with many many small files. And I want to understand what is going on under the hood for such tasks..