From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx1.redhat.com (ext-mx10.extmail.prod.ext.phx2.redhat.com [10.5.110.14]) by int-mx04.intmail.prod.int.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id o2QEGpLK029122 for ; Fri, 26 Mar 2010 10:16:51 -0400 Received: from mail-pz0-f188.google.com (mail-pz0-f188.google.com [209.85.222.188]) by mx1.redhat.com (8.13.8/8.13.8) with ESMTP id o2QEGoYt011918 for ; Fri, 26 Mar 2010 10:16:51 -0400 Received: by pzk26 with SMTP id 26so4972835pzk.6 for ; Fri, 26 Mar 2010 07:16:50 -0700 (PDT) Message-ID: <4BACC1D0.9090402@davidcoulson.net> Date: Fri, 26 Mar 2010 10:16:48 -0400 From: David Coulson MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: [linux-lvm] Auto PV scan w/ LVM Reply-To: LVM general discussion and development List-Id: LVM general discussion and development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , List-Id: Content-Type: text/plain; charset="us-ascii"; format="flowed" To: LVM general discussion and development I've got a couple of Clariion disk frames on which we performing cloning of LUNs for backups using HP-UX systems. Basically box A has a LUN or two, we clone it, and present it to box B - It mounts it, backs it up, then umounts it and we restart the cloning process... Nothing magical. I'm working towards replicating this process for Linux systems, and keep hitting a road block. The clone LUN is always presented to the backup server, however while it is syncing with the source LUN it is not available for IO directly. In this state multipathd marks both paths as failed, which I'm okay with: [root@rhtsutility02 ~]# multipath -ll 3600601608d211a00f4e21b978136df11 3600601608d211a00f4e21b978136df11 [size=20 GB][features="1 queue_if_no_path"][hwhandler="1 emc"] \_ round-robin 0 [prio=1][enabled] \_ 15:0:0:12 sdad 65:208 [failed][ready] \_ round-robin 0 [enabled] \_ 17:0:0:12 sdac 65:192 [failed][ready] Unfortunately, LVM seems to automatically pick up on PVs within the cloned LUN as soon as multipathd grabs it, so as soon as I do a 'vgscan' it hangs until I break the clone and present the cloned LUN to my backup box. So far I've basically excluded these cloned LUNs from lvm with a filter, however I do need to enable the VGs on them and mount LVs for backups. I'm not sure if switching out the filter all the time is the best way to go, but it doesn't look like LVM2's version of vgimport allows you to specify a PV device. Anyone had to deal with this before, or have an idea of a good way to deal with it? I agree it's a messy situation, but EMC is good at that :-)