ZFS Drive change best practice.

[Jeremy Chadwick]

On Wed, Nov 19, 2008 at 10:45:52PM +1000, Danny Carroll wrote:
> I need to migrate my ZFS drives from one bus to another.  As such they
> will be getting new device names.
> 
> I am pretty sure that if I do this with an export/import then it will
> just get the job done.
> 
> Does anyone know if there I need to take anything special into
> consideration, like perhaps maintaining the order of the drives?

Drive order does not matter, and drive label (e.g. adX or daX) does
not matter; "zpool import -a" will figure it out.

HOWEVER, there is a problem where ZFS can list the same drive label
twice or more in the members list.  Take a look at the last part of my
Wiki here -- you'll see two members with the same name.  This was
induced by moving cables between two different controllers:

http://wiki.freebsd.org/JeremyChadwick/ZFS_disk_upgrade_gone_bad

I sent mail to pjd@ about this, but didn't receive a response (which is
understandable given how busy he is).  I have no idea if the latest ZFS
commit on CURRENT fixes this problem.

Just something to keep in mind.

-- 
| Jeremy Chadwick                                jdc at parodius.com |
| Parodius Networking                       http://www.parodius.com/ |
| UNIX Systems Administrator                  Mountain View, CA, USA |
| Making life hard for others since 1977.              PGP: 4BD6C0CB |