Re: [Ips] iSCSI-specific unit attention conditions Tue, 31 March 2009 20:11 UTC

Return-Path: <>
Received: from localhost (localhost []) by (Postfix) with ESMTP id 0F0CD3A69AE for <>; Tue, 31 Mar 2009 13:11:12 -0700 (PDT)
X-Virus-Scanned: amavisd-new at
X-Spam-Flag: NO
X-Spam-Score: -6.599
X-Spam-Status: No, score=-6.599 tagged_above=-999 required=5 tests=[BAYES_00=-2.599, RCVD_IN_DNSWL_MED=-4]
Received: from ([]) by localhost ( []) (amavisd-new, port 10024) with ESMTP id b96f5MfLNOEy for <>; Tue, 31 Mar 2009 13:11:11 -0700 (PDT)
Received: from ( []) by (Postfix) with ESMTP id F33993A6810 for <>; Tue, 31 Mar 2009 13:11:10 -0700 (PDT)
Received: from ( []) by (Switch-3.2.5/Switch-3.1.7) with ESMTP id n2VKC7eL008612 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Tue, 31 Mar 2009 16:12:08 -0400 (EDT)
Received: from ( []) by (Tablus Interceptor); Tue, 31 Mar 2009 16:12:04 -0400
Received: from ( []) by (Switch-3.3.2mp/Switch-3.3.2mp) with ESMTP id n2VKC1ww003695; Tue, 31 Mar 2009 16:12:04 -0400
Received: from ([]) by with Microsoft SMTPSVC(6.0.3790.1830); Tue, 31 Mar 2009 16:12:01 -0400
X-MimeOLE: Produced By Microsoft Exchange V6.5
Content-class: urn:content-classes:message
MIME-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: quoted-printable
Date: Tue, 31 Mar 2009 16:11:34 -0400
Message-ID: <>
In-Reply-To: <18898.28621.87089.387064@gargle.gargle.HOWL>
Thread-Topic: [Ips] iSCSI-specific unit attention conditions
thread-index: AcmyN3muVtch7cfqQ4mDSuvM/lOx5QAA7X3A
References: <18898.26477.64898.577194@gargle.gargle.HOWL><> <18898.28621.87089.387064@gargle.gargle.HOWL>
To: <>, <>
X-OriginalArrivalTime: 31 Mar 2009 20:12:01.0303 (UTC) FILETIME=[F3B13A70:01C9B23C]
X-EMM-EM: Active
Subject: Re: [Ips] iSCSI-specific unit attention conditions
X-Mailman-Version: 2.1.9
Precedence: list
List-Id: IP Storage <>
List-Unsubscribe: <>, <>
List-Archive: <>
List-Post: <>
List-Help: <>
List-Subscribe: <>, <>
X-List-Received-Date: Tue, 31 Mar 2009 20:11:12 -0000

Maybe this is obvious to the T10 folks in the audience, but . . . Since
these unit attentions use an ASC of 3F, they indicate a change to the
operating state of the device.  No commands are affected.  From the
concise wording of the 05-406 proposal, it's hard to be sure what the
author intended, but it sounds to me like the target is telling the
initiator about a change in the membership of the portal group.

Might be caused by a configuration change, possibly by hot-plugging
another network interface card into the target system. 

DJ Brown

-----Original Message-----
From: [] On Behalf Of
Paul Koning
Sent: Tuesday, March 31, 2009 3:32 PM
Cc:; Black, David
Subject: Re: [Ips] iSCSI-specific unit attention conditions

>>>>> "Frederick" == Frederick Knight <Knight> writes:

 Frederick> My interpretation of the "update" part of the agenda was
 Frederick> that SAM-4 was an example (and that we should also include
 Frederick> SAM-3 and SAM-5 as part of the update list).  Therefore,
 Frederick> to add SPC to the update list is (in my opinion) within
 Frederick> the scope for the SCSI Update portion of this project.

 Frederick> Yes, it should be included in the charter (either
 Frederick> specifically, or by making clear the broader
 Frederick> interpretation of the "update").

Ok, that sounds good.

 Frederick> There is no person advocating these ASC/Q codes.  These
 Frederick> are ALREADY APPROVED ASC/Q codes, and the person that
 Frederick> caused them to become approved is no longer part of T10,
 Frederick> nor is that company a part of T10 at this time, so it will
 Frederick> be hard to find them and get them to do anything.

 Frederick> In my opinion, we should define their use, and let the
 Frederick> e-mail reviews make sure we get it right (or as good as we
 Frederick> can).  Partly because, contrary to the statement below,
 Frederick> the causes of all unit attention conditions are not
 Frederick> "clearly defined".

I was assuming the person doing the advocating would be the
appropriate one to do the defining.  If that person isn't around but
someone else wants to do the defining, that is fine, too.

Part of what bothers me is that I can't fathom what these codes are
intended for, or what the scenarios are when they might be generated,
or what conclusion an initiator is supposed to draw when it sees one.

The names vaguely suggest that they have something to do with
asynchronous logout, but that is already fully covered in the iSCSI
spec.  Itdoesn't require any unit attentions in the first place,
certainly not any iSCSI specific ones.

I would rather see these things go away, unless there is a good
argument made that there is something missing in iSCSI that needs to
be added, and these codes are part of the solution.  The fact that T10
already approved them isn't a reason to add them to iSCSI.


Ips mailing list