From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx1.redhat.com (mx1.redhat.com [172.16.48.31]) by int-mx1.corp.redhat.com (8.13.1/8.13.1) with ESMTP id l3EG735U027695 for ; Sat, 14 Apr 2007 12:07:03 -0400 Received: from extmail.dtnet.de (extmail.dtnet.de [87.193.12.202]) by mx1.redhat.com (8.13.1/8.13.1) with ESMTP id l3EG71DW005094 for ; Sat, 14 Apr 2007 12:07:02 -0400 Message-ID: <4620F6F1.8020906@dtnet.de> Date: Sat, 14 Apr 2007 17:44:49 +0200 From: Daniel Schwager MIME-Version: 1.0 Subject: Re: [linux-lvm] Limitation: Snapshots does not work in cluster enviroment ? References: <4620D7E3.9090609@dtnet.de> <20070414145250.GI26983@agk.fab.redhat.com> <4620E73F.50100@dtnet.de> <20070414152407.GK26983@agk.fab.redhat.com> In-Reply-To: <20070414152407.GK26983@agk.fab.redhat.com> Content-Transfer-Encoding: 7bit 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 Alasdair G Kergon schrieb: >> So, i want to use snapshot1 on server1, snapshot2 on server2. The >> original LV (where the snapshot is created from) is not in use (not mounted on any >> server) >> .. > I think the userspace LVM code could be tweaked to support this > configuration. Until then, you'll need to activate the snapshots > manually using dmsetup directly. > This would be fine. > > Userspace changes we'd need for the tools (dmsetup) to support this: > Permit a snapshot to be activated without its corresponding origin. > - requires a snapshot exclusive lock (already supported) > - requires an origin lock that prevents any node having origin active > (implementation needs more thought but it should be possible) > > So, thank you very much for your detailed explanation. Would an implementaion change on "dmsetup" also solve the "Limitation of 32 snapshots" ? Or is there a another possibility to fix/workaround this topic ? regards Danny