From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx1.redhat.com (ext-mx01.extmail.prod.ext.phx2.redhat.com [10.5.110.5]) by int-mx10.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id oA51QcJ8016019 for ; Thu, 4 Nov 2010 21:26:38 -0400 Received: from cdptpa-omtalb.mail.rr.com (cdptpa-omtalb.mail.rr.com [75.180.132.120]) by mx1.redhat.com (8.13.8/8.13.8) with ESMTP id oA51QN31019811 for ; Thu, 4 Nov 2010 21:26:23 -0400 Message-ID: <4CD35D3E.5030200@cfl.rr.com> Date: Thu, 04 Nov 2010 21:26:22 -0400 From: Phillip Susi MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: [linux-lvm] LVM + raid + san 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: linux-lvm@redhat.com I was wondering about using LVM to manage disks on a SAS SAN with one or more multi disk enclosures and multiple host servers. It looks like LVM has the capability to manage all of the disks as PVs and coordinate between the hosts to allow any given host to mount any given lv at any time, but I could not figure out how raid would fit into the picture. Ideally you want to group the disks into a few raid5 or raid6 arrays, and then slice them up into logical volumes. As far as I know the device mapper raid5/6 support is still highly experimental so most people just use mdadm to create a raid array and use that as an lvm pv, but in a san environment, you wouldn't be able to activate the raid pv on more than one host would you? Can this be done with mdadm, and/or how is the dm raid5/6 support coming so that lvm can directly manage the individual disks as pvs while still having fault tolerance?