Booting from ZFS raidz

[Ollivier Robert]

According to George Hartzell:
> Which jsut means that you need a populated boot directory at the top
> of the tank (e.g. /data/boot).  If you're using the
> create-zfsboot-gpt.sh file that was posted here recently, you'll need
> to rework it a bit, since it puts the root dir at /data/ROOT/data.

OK, following this, I managed the boot code to find loader & loader.conf.
It stops when it can't find the root I want it to boot from though.

The ? prompt shows me all devices (da{0,1,2}, da{0,1,2}p{1,2} and
label/swap) but trying to use zfs:whatever does not seem to work.

loader.conf is very small:
-----
zfs_load="YES"
geom_label_load="YES"
vfs.root.mountfrom="zfs:tank/ROOT/tank"
-----

I did
zfs set mountpoint=/tank/ROOT/tank tank/ROOT/tank (aka the real root)

the other fs are in their usual place
zfs set  mountpoint=/usr tank/usr
zfs set  mountpoint=/var tank/var

Any other ideas.  I'll try to summarize here and on the wiki when I'm done.
-- 
Ollivier ROBERT -=- FreeBSD: The Power to Serve! -=- roberto at keltia.freenix.fr
In memoriam to Ondine : http://ondine.keltia.net/