From mboxrd@z Thu Jan 1 00:00:00 1970 From: Hannes Reinecke Subject: Re: Error handling on FC devices Date: Wed, 28 Nov 2012 08:09:56 +0100 Message-ID: <50B5B8C4.1040503@suse.de> References: <50AA290F.8000105@suse.de> <50B3EDEA.40008@emulex.com> <1354046601.4420.14.camel@localhost.localdomain> <94D0CD8314A33A4D9D801C0FE68B40294CCFD463@G9W0745.americas.hpqcorp.net> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Received: from cantor2.suse.de ([195.135.220.15]:55826 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751126Ab2K1HKC (ORCPT ); Wed, 28 Nov 2012 02:10:02 -0500 In-Reply-To: <94D0CD8314A33A4D9D801C0FE68B40294CCFD463@G9W0745.americas.hpqcorp.net> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: "Elliott, Robert (Server Storage)" Cc: "emilne@redhat.com" , "James.Smart@emulex.com" , SCSI Mailing List , Andrew Vasquez , Chad Dupuis , James Bottomley On 11/27/2012 09:29 PM, Elliott, Robert (Server Storage) wrote: > There is a new command in SPC-4 called REMOVE I_T NEXUS that is inten= ded to help > that situation. REMOVE I_T NEXUS lets the application client use=20 a good I_T nexus > to abort commands that were being processed on a bad I_T nexus,=20 so it can safely > re-issue those commands on the good I_T nexus without worrying=20 that the original > commands might resume. > > In contrast: > - the ABORT TASK, ABORT TASK SET, and CLEAR TASK SET must use the sam= e I_T nexus > as the commands being aborted, so are not viable if that I_T=20 nexus is bad > - LOGICAL UNIT RESET aborts commands from every I_T nexus, so in addi= tion to > aborting commands from the bad I_T nexus it also affects=20 commands on the > good I_T nexus > Hmm. Nice in principle, but the problem here is that we cannot=20 guarantee the nexus is still intact. So one would need to implement this in the HBA firmware; the=20 firmware would need to be able to process the TMF, and do the=20 appropriate things for the FC stack like dropping the rport etc. Good idea, though. James, Andrew, Chad? Any chance of having a firmware supporting REMOVE IT-NEXUS ? Cheers, Hannes --=20 Dr. Hannes Reinecke zSeries & Storage hare@suse.de +49 911 74053 688 SUSE LINUX Products GmbH, Maxfeldstr. 5, 90409 N=C3=BCrnberg GF: J. Hawn, J. Guild, F. Imend=C3=B6rffer, HRB 16746 (AG N=C3=BCrnberg= ) -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html