Time Machine • Are Time Machine backups only possible on the "public" share?

I created a new share for Time Machine backups (TimeMachineBackups)and added this to the Backup->Time Machine list of Authorised Directories. I also created a new user "tm-user" with read/write access to the Time Machine share and was able to configure this as a destination target in the macOS Time Machine settings.

However, a few seconds are starting, the backup errors out with this following message:

"Time Machine couldn’t complete the backup to “TimeMachineBackups”
The backup disk image could not be created.

I can see that some files are created in the share under a new folder with a GUID-like name each time a backup is attempted, e.g.

9A39CA87-XXXX-XXX-XXX-XXXX.purgable
token
> mapped
lock
info.plist

This folder is owned by the "tm-user", but clearly this user seems to be unable to carry out the actual backup. tm-user has read/write permissions, and I've also tried applying the folder permissions to all subdirectories.

Any idea what is going on?

Do TM backups only work in the public folder? If so, why is this folder any different to other shared folders?

Thanks

Statistics: Posted by johngwheeler — Today, 10:06

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