[OpenIndiana-discuss] Recovering from power loss on USB ZFS pool?

[Andrew Gabriel]

In my experience, one USB stick usually works OK.
Multiple USB sticks all accessed together, and you usually find the 
transport to all of them goes up and down like a yoyo, as though 
something was getting the threading of the connections across USB 
screwed up. (This is a shame because I'd love to use it to mock up a 
storage array for ZFS demos.)

IIRC, this issue started with a new USB framework early in Solaris 10, 
and is still like that in current Solaris 11.

USB disks can work better than USB sticks, but I haven't ever tried a 
direct substitution in the same environment where USB sticks fail, so I 
don't know if that's universally true.

Some USB sticks have only limited command support. If you get hangs when 
trying to use only one USB stick at a time, add the following to 
/kernel/drv/scsa2usb.conf:

attribute-override-list="vid=* reduced-cmd-support=true";

and then "update_drv -f scsa2usb" (or reboot). However, this does 
nothing to fix the multiple USB sticks issue above. (You can make this 
option selective for specific USB stick models only - see the comments 
in the file.)


On 28/03/2014 15:04, Michael Stapleton wrote:
> I'm not sure when things changed, but way back in the OpenSolaris days,
> I had the root drive in my laptop mirrored to an external USB drive.
> I never had problems back then. I would do a demonstration where I would
> remove the USB drive while the laptop was up and running, and then plug
> the USB submirror into another laptop and boot from it.
> Never had a problem. I could even reattach the USB drive to my laptop
> and it would resilver automatically.
>
> Is the problem ZFS or USB or FMA? no idea. But the was a regression of
> sorts.
> I don't think Solaris11 suffers from this.
>
>
> Mike

-- 
Andrew Gabriel