I have been waiting for V12 because of the Veeam Taper Server component for Linux. I have been testing things today and hit a unfortunate problem.
The Tape server cannot be installed on a Linux server that also offers Immutability on XFS. This happens because the immutability option for XFS filesystems is only available if you use a hardened linux with signle use sign in - but the Tape server role cannot be installed on a single use sign-in linux

I get that a "non hardened" linux is not as impenetrable, but why remove the immutable option on XFS if it's not running with a single use signin?
Is there any chance Veeam will adopt the tape server role to run on a hardened linux? I see no reason why that should not be possible?
Alternatively - is there a way to enable immutability settings in Veeam even if it's only a standard Linux based XFS repository?
Having the tape drive directly on the repository not only saves hardware and management/maintenance, but also improves performance for tape backups.