From mboxrd@z Thu Jan 1 00:00:00 1970 From: Hannes Reinecke Subject: Re: [PATCH] scsi: return TARGET_ERROR when a device has been disconnected Date: Thu, 16 Aug 2012 16:59:10 +0200 Message-ID: <502D0ABE.1010709@suse.de> References: <1345099208-31687-1-git-send-email-hare@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Received: from cantor2.suse.de ([195.135.220.15]:56975 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753804Ab2HPO7M (ORCPT ); Thu, 16 Aug 2012 10:59:12 -0400 In-Reply-To: Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: Michael Christie Cc: linux-scsi@vger.kernel.org, James Bottomley On 08/16/2012 04:53 PM, Michael Christie wrote: >=20 > On Aug 16, 2012, at 1:40 AM, Hannes Reinecke wrote: >=20 >> When we receive a sense code of >> NOT READY, LOGICAL UNIT NOT SUPPORTED >> the device has been disconnected and any retry on other paths >> would be pointless. So return TARGET_ERROR here. >=20 >=20 > What target is this with? HP EVA. > What about {ILLEGAL_REQUEST, LOGICAL UNIT NOT SUPPORTED}? > Would you want to do the same behavior for that error? >=20 Yes, presumably. > I ask because I have seen targets return {ILLEGAL_REQUEST, LOGICAL U= NIT NOT SUPPORTED} > when you only unexport the LUN from a path/port on the target. > I was wondering if some might do the same for {NOT_READY, LOGICAL UNIT NOT SUPPORTED}? > In those cases, we would not want multipath to fail IO. >=20 That's exactly the use-case. When you unexport a target you're getting the "LUN NOT SUPPORTED" message. And you'll need to return the error to the upper layers, as you might want to disconnect the device (eg do a 'rescan-scsi-bus.sh') and you'll want to finish any program quickly here. > In these type of cases should the target be returning something else? >=20 No, that's okay. We should be modifying it to encompass both. Cheers, Hannes --=20 Dr. Hannes Reinecke zSeries & Storage hare@suse.de +49 911 74053 688 SUSE LINUX Products GmbH, Maxfeldstr. 5, 90409 N=FCrnberg GF: J. Hawn, J. Guild, F. Imend=F6rffer, HRB 16746 (AG N=FCrnberg) -- 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