Sometimes, patience is a virtue....

I had this yesterday (and today) as I tried to hunt down a "Bug" in my NAS VM. The drives for the zfs pool disappeared after I rebooted the host.

I first thought I made a config error or the update changed some settings/naming etc. But as the VM directly accesses the SAS-HBA connecting to the drives that couldn't be it, could it? So I checked everything and after a second reboot all devices connected to that HBA were gone and I started to worry a lot about my data. Most of it was redundant so it should not be a problem if I lose one pool - but some were not.

I tried another reboot and checking the HBA config/bios and while it loaded the config ... it just crashed and rebooted from the BIOS? What the ...?

A lot of googling later I found a small forum where somebody posted just a few lines that helped me out here. They had several Servers with the same HBA (LSI 9308) which they decomissioned after they noted all of them causing problems - because the don't handle reboots well... If you power it off and keep it some minutes unpowered before turning it back on again it just works fine. Guess I gonna need to learn some more patience (and look for a HBA replacement it seems).