ZFS attaching direct access drives as Scsibus#target#drive#

[Max Laier]

On Tuesday 14 October 2008 21:56:01 Daniel Jameson wrote:
> I'm in the process of building several zfs pools for a backup-server,
> the machine has 2 24 port sata 3 controllers and 48 1TB drives for
> storage.  I've done a little testing and found that building  a pool by
> using the da# device names can be inconsistent.  For example if a device
> is lost from the first controller and the box is re-booted all the da#s
> shuffle up,  which creates problems with adjacent pools, and the
> potential for catastrophic failure. In the Sun documentation zpool
> allows a pool to be built by using S#T#D# (Scsibus Target Drive) syntax,
> when I attempt it in FBSD It returns:" cannot use '/dev/c0t0d0': must be
> a GEOM provider" does anyone know a way to statically map a
> scsibus/target/drive to a specific da# or a fix to allow specific drives
> by target numbers to be added to a zpool?

I though there was some magic to map devices by UID ... but I can't seem to 
find references to it right now.  You can use glabel, however, and build the 
pool from the labeled devices instead.

glabel disk0 /dev/da0
glabel disk1 /dev/da1
...

zpool create tank /dev/label/disk0 /dev/label/disk1 ...

This will loose one sector at the end, but should otherwise have no negative 
effects.  But you can juggle around devices as much as you like.

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