Skip site navigation (1)Skip section navigation (2)
Date:      Sun, 12 Oct 1997 09:44:26 +0200
From:      Stefan Esser <se@FreeBSD.ORG>
To:        Kenneth Merry <ken@plutotech.com>
Cc:        scsi@FreeBSD.ORG, Stefan Esser <se@FreeBSD.ORG>
Subject:   Re: Trouble with dump on ncr
Message-ID:  <19971012094426.47163@mi.uni-koeln.de>
In-Reply-To: <199710120615.AAA18578@pluto.plutotech.com>; from Kenneth Merry on Sun, Oct 12, 1997 at 12:15:56AM -0600
References:  <19971011091605.32335@mi.uni-koeln.de> <199710120615.AAA18578@pluto.plutotech.com>

next in thread | previous in thread | raw e-mail | index | archive | help
On 1997-10-12 00:15 -0600, Kenneth Merry <ken@plutotech.com> wrote:
> > The start unit command should instead be issued from the
> > recovery code in the generic SCSI layer, IMHO, whenever 
> > the return status from the SCSI card driver indicates a
> > drive has (been) stopped in an attempt to recover from
> > that situation.
> 
> 	FWIW, that's what the new CAM SCSI code does.  The da (i.e. sd)
> driver does a read capacity upon open.  If the read capacity returns with
> 0x04, 0x02 ("Logical unit not ready, initializing cmd. required"), the error
> recovery code issues a start unit command to the drive.  

I downloaded that code, but did not have time 
to look into it in detail. It is unfortunate,
that many parts outside /sys have to me made
aware of the CAM driver, IMHO.

> 	One interesting thing about that, though..  Apparantly not all
> drives return 0x04,0x02 when they aren't spun up.  I ran into some Quantum
> Fireball ST (Stratus) drives that return 0x04,0x0b when they aren't spun
> up.  Strange, 'eh?  That sense code qualifier isn't in the SCSI specs (not
> even SCSI-3), and it isn't in Quantum's documentation on the drive.

Well, I guess it is save to just exclude those
ASCQ values for ASC 0x04 that indicate a simple
motor start command is not sufficient (0x04/0x03
surely does not ask for a START STOP UNIT command :)

How about "issue a start unit command for ASC 0x04
and ASCQ equal 0x02 or greater-equal 0x09. Can't
see how that could cause problems ...

Regards, STefan



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?19971012094426.47163>