[OpenIndiana-discuss] Booting from a drive detached from a ZFS mirrored root pool

[Jim Klimov]

On 2013-01-27 01:04, Reginald Beardsley wrote:
> Because I can't boot from 3 TB drives, I'm trying to sort out plan B for configuring my N40L.
>
> If I stick the 250 GB disk that came w/ the system in the ODD slot and use that for the root pool w/ a 4x3 TB RAIDZ, what happens if my root pool disk fails?  ZFS keeps  a lot of state information in places I don't know about.

Actually, not much should be lost - if you don't keep needed data
(including unique setups, root scripts and log/note files, etc.)
on the single disk. The pool disks (your 4*3Tb) are self-contained
and can be imported by another OS installation that would come on
another root disk. You might want to protect the singular root
disk from spontaneous bit errors by forcing "copies=2" or even
"copies=3", preferably from the start (i.e. by manually creating
the rpool with this option). This has saved me quite a bit on a
system with a flaky root disk which had otherwise failed to boot
once or twice, before reformatting it with a new rpool with set
copies=2, due to lost pieces of system files.

You might also benefit from disk racks that fit into an ODD slot
and house several 2.5" disks (2, 4, 6 available) or a 3.5"+2.5"
couple...

HTH,
//Jim