(I removed the Unassigned Devices and Recycle Bin sections from the above quote in an attempt at brevity.)
The Time Machine issue is so frustrating, 'cause what seems to fix it for others does nothing for me. I emptied my smb_extra.conf and replaced it with that one and... no joy. I'm trying to come up with anything that might make the same settings work for others but not me and... this sounds like insanity to me, but the only thing I can come up with is maybe `fruit:metadata = stream` is the only relevant part of the config, and not because the metadata needs to be stored as xattrs instead of in a netatalk-compatible way, but because changing the location effectively clears the metadata... which wouldn't happen for me because that was a setting I played around with previously, so I already have metadata stored in both formats.
I haven't been able to test this theory yet... and it'll be a few days until I can test it. And honestly, I don't think it's likely... but I think the rest of the config is a red herring.
`fruit:nfs_aces = no` is already set by unraid in rc3.
`fruit:zero_file_id = yes` is the default according to the documentation.
`fruit:encoding = native` changes how unicode in filenames gets stored, but there are no files with unusual characters in Time Machine disk image file names (unless maybe if your computer name contains them)
`spotlight backend = tracker` changes the spotlight index source for server-side spotlight searches to Gnome Tracker, which isn't installed or configured on unraid. I don't think setting that should fix anything, but apparently it fixes spotlight... but Time Machine doesn't need spotlight for the share anyway.
`veto files = /._*/.DS_Store/` blocks the creation of .DS_Store files and hides existing ones along with the files that store resource forks from SMB users. I don't think that's a problem for Time Machine and I'd rather have DS_Store working, so I hope that's not the solution.
That leaves `fruit:metadata = stream` which changes how macos xattrs are stored and `vfs objects`. The only vfs object listed in that config that we aren't already loading on each share is acl_xattr, and that's for supporting Windows access control lists, which shouldn't be relevant here.
So yeah. Unless anyone comes up with a better idea before I get a chance, I think I'm gonna try deleting the xattrs from the Time Machine backup and see if that helps. Honestly, I doubt it will, but... I got nothin'.