Why not just name the cam-ata devices the same as the old, names?

[Daniel Kalchev]

This labeling issue has intrigued me recently, as ZFS has become more 
mature on FreeBSD.

With ZFS, although you may have the same pool names on disks, you will 
not import the wrong zpool (unless you boot off it somehow) if you 
happen to have two pool with the same name in the system. The zpool has 
it's UUID and the zpool name is just for user's convenience.

I believe, we could invent/adopt something similar for UFS labels as well.

Now, the easiest answer for this device renaming problem is: use UFS 
labels. Or disk labels, as Freddie suggested. Or GPT partition labels. 
Or use GUUIDs instead (GPT or UFS) if you are paranoid.

Why would it be a problem that UFS labels are gone, when you newfs the 
filesystem? Our intention to use labels is to preserve mount points 
across reboots, possible on different hardware (HBA). You don't keep the 
contents of the filesystem when you newfs it, so you may well provide 
newfs with the appropriate -L label. Or use new label if you will use 
the filesystem for a different purpose/mountpoint.

What should be done, ideally before the 9.0 release is to find some sane 
resolution method of what happens when you happen to have two (for 
example) 'root' UFS labels during boot/mount time.

Daniel