Skip site navigation (1)Skip section navigation (2)
Date:      Sat, 23 Nov 1996 20:50:07 -0600 (CST)
From:      Joe Greco <jgreco@brasil.moneng.mei.com>
To:        andrew@pubnix.net
Cc:        isp@freebsd.org
Subject:   Re: News server disk Striping (more)
Message-ID:  <199611240250.UAA12755@brasil.moneng.mei.com>
In-Reply-To: <Pine.BSF.3.91.961123211959.6459H-100000@guardian.fortress.org> from "Andrew Webster" at Nov 23, 96 09:21:16 pm

index | next in thread | previous in thread | raw e-mail

> I had posted this about a week ago, but no suggestions, I did notice 
> however that when it locks up a drive and SCSI controller both have their 
> activity lights lit.  
> 
> Bugs in the SCSI code under heavy load?
>
> The hardware consists of a pair of 2.1 ST32151W drives on an AHA-2940UW 
> controller.

I have (very!) intermittently seen the same thing happen with ST-31055N's
and NCR-810 controllers - the drive appears to "wedge".  The machine in
question is certainly under heavy load, and seems to develop stuck drive
syndrome about once a month.

Since the 31055N and 32151W's are cousins, and the NCR-810 and AHA-2940UW
are totally different drivers (at least pre-2.2), this tends to confirm my
suspicion that this may be some sort of obscure drive firmware bug.

An additional data point may be that I have _only_ seen this on heterogeneous
drive chains; i.e. I have not seen a 31055N that is on a chain with a 32550N
and 15150N lock up.  The lock ups only seem to happen on a homogeneous drive
chain.  (Sample set is three dozen drives, soon two dozen more).

I think it is some low level SCSI drive bogon, probably not (strictly) a
FreeBSDism.  It may be possible that FreeBSD could "work around" this with
some sort of timeout and recovery strategy that may not currently exist.

... JG


home | help

Want to link to this message? Use this
URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?199611240250.UAA12755>