From mboxrd@z Thu Jan 1 00:00:00 1970 From: Hannes Reinecke Subject: Re: multipath-tools causes path to come back as different block device Date: Fri, 20 Jul 2007 16:40:11 +0200 Message-ID: <46A0C94B.4010905@suse.de> References: <469FEBBB.5040507@csupomona.edu> <46A0631F.4030404@suse.de> <20070720115315.GA26421@bogon.ms20.nix> Reply-To: device-mapper development Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Return-path: In-Reply-To: <20070720115315.GA26421@bogon.ms20.nix> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: dm-devel-bounces@redhat.com Errors-To: dm-devel-bounces@redhat.com To: device-mapper development List-Id: dm-devel.ids Guido Guenther wrote: > Hi Hannes, > On Fri, Jul 20, 2007 at 09:24:15AM +0200, Hannes Reinecke wrote: >> Hmm. multipathd really should react to the 'remove' events for sdX. >> Checking ... >> >> Looks as if it does. And it even is supposed to stop the path checker. >> >> Care to run multipathd with full debugging (ie -v 4) and post the outp= ut? >> My guess is that somehow the path checker is not stopped and the fd is= kept >> open, so that the device is not released properly. > This even happens with no multipathd running on a Clariion with qla2xx. > So multipathd can't be at fault here, can it? Also with multipathd > running the device nodes in /dev/ and the sysfs nodes in /sys/block get > removed properly (at least it looks like to me). Any hints where else t= o > start digging? Removing from /dev and /sys in not sufficient, sadly. The memory is only released after the last reference has gone. So all fd's have to be closed (ie multipathd and the path checkers have to have this path disabled) and no device-mapper table must reference it. So easiest way is infact to have multipathd run with -v 4, as this will tell you exactly if multipathd has stopped the path checker. The device-mapper tables can be checked manually with dmsetup. 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: Markus Rex, HRB 16746 (AG N=FCrnberg)