[OmniOS-discuss] disk failure causing reboot?

[Jeff Stockett]

Hi Dan,

The pool is made up of 36 disks - 6 x 6 raidz2 vdevs with some SSDs for l2arc and slog.  I already replaced the drive and the rebuild is nearly done, but I was mostly curious why a disk failure would cause a reboot?  I get that it was apparently hanging the pool up, and that according to some posts I read the developers seem to think it is better the panic/dump/reboot than leave it hung until someone notices, but wouldn't it really be better just to drop the failed drive out of the array? Is it because the system in question is using a SAS expander or is this only expected behavior sometimes depending on how the drive fails?  I guess I might expect this with consumer grade SATA drives, but wasn't expecting it with $$$ enterprise SAS drives.

Thanks,  Jeff

-----Original Message-----
From: Dan McDonald [mailto:danmcd at omniti.com] 
Sent: Monday, May 18, 2015 11:33 AM
To: Jeff Stockett
Cc: omnios-discuss
Subject: Re: [OmniOS-discuss] disk failure causing reboot?


> On May 18, 2015, at 2:25 PM, Jeff Stockett <jstockett at molalla.com> wrote:
> 
> A drive failed in one of our supermicro 5048R-E1CR36L servers running omnios r151012 last night, and somewhat unexpectedly, the whole system seems to have panicked.

The panic was done for protection of your pool:

> May 18 04:44:36 zfs01 genunix: [ID 918906 kern.notice] I/O to pool 'dpool' appears to be hung.

<SNIP!>

>  
> The disks are all 4TB WD40001FYYG enterprise SAS drives.  Googling seems to indicate it is a known problem with the way the various subsystems sometimes interact. Is there any way to fix/workaround this issue?

Pull the drive.  I'm assuming you have a raidz or mirrored setup where you can do that, right?  Or is it a question of finding *which* drive failed?

Dan