From mboxrd@z Thu Jan 1 00:00:00 1970 From: Phillip Susi Subject: Re: LVM on dmraid breakage Date: Thu, 02 Aug 2007 17:50:51 -0400 Message-ID: <46B251BB.1010004@cfl.rr.com> References: <46B0EAEF.6090305@cfl.rr.com> <20070802065012.GA28687@percy.comedia.it> <46B1B5E1.1050406@redhat.com> Reply-To: "ATARAID (eg, Promise Fasttrak, Highpoint 370) related discussions" Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <46B1B5E1.1050406@redhat.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: ataraid-list-bounces@redhat.com Errors-To: ataraid-list-bounces@redhat.com To: "ATARAID (eg, Promise Fasttrak, Highpoint 370) related discussions" Cc: device-mapper development , linux-lvm@redhat.com List-Id: dm-devel.ids Bryn M. Reeves wrote: > But device-mapper already opens devices exclusively when a target claims > them. > > The problem here sounds more like it's down to ordering; LVM2 is being > given a chance to scan the devices & build LVs / claim devices before > dmraid gets a look at them. I think the "exclusive" open only prevents you from mounting a filesystem on the device. It does not stop you from opening the device and accessing it from user mode, nor does it apparently prevent dm from (re)using the device. The problem is that lvm is looking at the physical disks at all. It needs to scan the dmraid device, not the underlying disks.