From mboxrd@z Thu Jan 1 00:00:00 1970 From: Clay Haapala Subject: Re: Request for review of Linux iSCSI driver version 4.0.0.1 Date: Wed, 03 Dec 2003 14:45:02 -0600 Sender: linux-scsi-owner@vger.kernel.org Message-ID: References: <03120118001300.08627@naveenb-lnx.cisco.com> <03120217260300.01630@naveenb-lnx.cisco.com> <1070383028.2345.8.camel@mulgrave> <03120319364802.02505@naveenb-lnx.cisco.com> <1070464184.1771.33.camel@mulgrave> <20031203175417.GA893@beaverton.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from sj-iport-4.cisco.com ([171.68.10.86]:27723 "EHLO sj-iport-4.cisco.com") by vger.kernel.org with ESMTP id S261567AbTLCUpH (ORCPT ); Wed, 3 Dec 2003 15:45:07 -0500 In-Reply-To: <20031203175417.GA893@beaverton.ibm.com> (Mike Anderson's message of "Wed, 3 Dec 2003 09:54:17 -0800") List-Id: linux-scsi@vger.kernel.org To: James Bottomley Cc: naveenb@cisco.com, Roman Zippel , hch@infradead.org, SCSI Mailing List , davmyers@cisco.com On Wed, 3 Dec 2003, Mike Anderson outgrape: > Clay Haapala [chaapala@cisco.com] wrote: >> >> Naveen, is it intended that the iSCSI driver retry when the 0B/4705 >> is detected, or will that sense code and COMMAND ABORT be passed up >> to the SCSI layers for retry? >> >> James, et al, do the SCSI layers retry on COMMAND ABORT? >> >> I don't believe the SCSI layers retry on HARDWARE ERROR -- this is >> a difference between how Solaris and Linux operate, for example, >> unless I am misunderstanding or have obsolete information. -- > > scsi_check_sense will return NEEDS_RETRY for: > - ABORTED_COMMAND > > - NOT_READY and UNIT_ATTENTION under the expecting_cc_ua and > becoming ready case. > > - MEDIUM_ERROR > > If the allowed count has not been exceeded the command will be > retried. > > -andmike A couple of related SCSI (not necessarily iSCSI) questions: "If the allowed count has not been exceeded" - The first two commands after a connection has been estabilished will fail with Unit_Attention. What if that first command then also gets a crc error (Aborted_command)? Will the retry count be large enough? Does the retry also apply to tape? Without proper tape error recovery, retrying the command could result in duplicate records written to tape. -- Clay Haapala (chaapala@cisco.com) Cisco Systems SRBU +1 763-398-1056 6450 Wedgwood Rd, Suite 130 Maple Grove MN 55311 PGP: C89240AD Active dissent has been part of American government since the Boston Tea Party, and will be until its end.