Root volume renumbered unexpectedly, no longer boots

[Morgan Wesström]

> 48 disks, actually. :)   Half of those are on an external JBOD connected
> via an LSI FC controller.  This server is significantly older than my
> association with it, so I'm uncertain about how the internal 24 drives are
> connected.  If it helps, dmesg only reports ses0 and ses1 drivers.  The
> boot disk and the first 24 ZFS drives are all on ses0.  I think that
> implies only two controllers in use, not three.
> 

Yeah, I see now that your mainboard has a SAS controller in addition to 
the Intel ICH10 controller. That BIOS setting I suggested would only 
affect disks attached to the Intel controller. The SAS controller should 
have it's own option BIOS settings, available through some key combo 
during boot. I have no experience with these controllers though so I 
couldn't tell if something in their settings suddenly made them report 
disks in a different order. Hopefully someone who knows how they work 
will read this and help you.

/Morgan