From mboxrd@z Thu Jan 1 00:00:00 1970 From: christophe varoqui Subject: Re: [dm-devel] [multipath] SCSI device capacity mess Date: Sat, 30 Oct 2004 09:21:10 +0200 Sender: linux-scsi-owner@vger.kernel.org Message-ID: <1099120870.27274.37.camel@zezette> References: <1098833278.4914.24.camel@zezette> <20041027081713.GC32712@marowsky-bree.de> <1098903759.12464.32.camel@zezette> <1098914250.1588.1.camel@mulgrave> <20041028113728.GT32712@marowsky-bree.de> <20041028181436.GA18874@beaverton.ibm.com> <20041028182154.GY32712@marowsky-bree.de> <20041030004131.GA29908@beaverton.ibm.com> Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Return-path: Received: from smtp5.wanadoo.fr ([193.252.22.26]:52036 "EHLO mwinf0504.wanadoo.fr") by vger.kernel.org with ESMTP id S263633AbUJ3HVP (ORCPT ); Sat, 30 Oct 2004 03:21:15 -0400 In-Reply-To: <20041030004131.GA29908@beaverton.ibm.com> List-Id: linux-scsi@vger.kernel.org To: device-mapper development Cc: Lars Marowsky-Bree , "linux-scsi@vger.kernel.org" > > I'm just saying we should stop on the first failed command (TUR) and not > > retry to read all 64 sectors regardless. I can live with one error per > > passive path, but 64 really kills the logs. > > That makes sense. > > What is the result of the TUR? I did not see any information about it in other posts in this thread. > the tur checker in multipath-tools report ghosts as failing. > We should change state somehow if the TUR failed or was not ready, maybe > call set_media_not_present(), or maybe change the sdev state to > SDEV_OFFLINE - though that might cause extra logging. > > We might not normally every hit this since the scan (INQUIRY failure) > would likely prevent the device from showing up at all. scsi_id and INQUIRY succeed on ghost paths, which allow multipath to group them with valid paths to the same LU. > Plus, we only call sd_spinup_disk() during discovery and not on open, > unlike the calls to sd_media_changed(). > Would it be workable to add a scsi_devinfo flag for devices with ghosts. If this flag is set and state is down, open calls sd_media_changed(). The multipath-tools and device-mapper will try as hard as possible to avoid opening those device if not necessary, by grouping them in a low priority path group. regards, -- christophe varoqui