Yes. Although I don't recommend using UFS and ZFS on the same disk. But it's perfectly fine to add a 4 disk RAID-Z ZFS pool for example to an existing UFS installation.I have FreeBSD 12-Release running with a ufs, can I add a zfs partition to it?
This was my set up for a long time when ZFS was still very new, I wasn't comfortable yet to use it as a root filesystem.And does it make sense?