I am impressed…. my gmirror array continued to work even after the drives were renamed from da20 and da24 to ada0 and ada1. This happened when I tried out the ahci(4) for my SATA drives.
It’s the type of thing I’m striving for soon in my ZFS array.
All this started when I wanted to find out about making my ZFS array more resilient. See http://docs.freebsd.org/cgi/getmsg.cgi?fetch=663685+0+current/freebsd-stable (which is the top level post of the above mentioned link).
I’d have to say that ZFS will do as gmirror, if you shuffle your hard drives, it’ll find them back automagically, no need to glabel them.
It did. See http://dan.langille.org/2011/04/05/zfs-benchmarking-ideas/