Re: aic94xx or libsas crash on X7DB3 supermicro with enclosure and sata drives

["Krzysztof Błaszkowski" <kb@sysmikro.com.pl>]

Hi Darrick,

On Monday 03 December 2007 20:36, Darrick J. Wong wrote:
> On Mon, Dec 03, 2007 at 05:09:54PM +0100, Krzysztof B??aszkowski wrote:
> > I noticed also another failure when i removed a drive. The event was not
> > notified by anything (ie the block device and corresponding sg were
> > registered) so i run dd on this truly "virtual" drive.
> >
> > dd reached D state (as well as scsi_wq) . i think it shouldn't happen no
> > matter it was AIC failure or LSI expander failure.
>
> "It's wireless!" ;)

yep :) and energy from positive thinking spins disk's plates ;) 

>
> Seriously, though, it's a good idea to tell the kernel that you're
> about to unplug a disk before actually doing it:
>
> echo 1 > /sys/block/sdX/device/delete
>
> This way, the kernel can tell the disk to flush its caches long before
> power actually gets removed.  Otherwise, the device removal code can
> get hung up just like you observed, and whatever's in the write cache
> may or may not actually get written to the media.
>

imagine just raining Monday and someone who put hand on the drive thus he had 
to reboot whole box.

Thanks,
Krzysztof
> --D