From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from agk.surrey.redhat.com (agk.surrey.redhat.com [172.16.10.74]) by pobox.surrey.redhat.com (8.12.8/8.12.8) with ESMTP id j6TKlvRm021386 for ; Fri, 29 Jul 2005 21:47:57 +0100 Received: from agk by agk.surrey.redhat.com with local (Exim 4.34) id 1Dyblt-0003VM-DO for linux-lvm@redhat.com; Fri, 29 Jul 2005 21:47:57 +0100 Date: Fri, 29 Jul 2005 21:47:57 +0100 From: Alasdair G Kergon Subject: Re: [linux-lvm] Progress on LVM2 snapshots Message-ID: <20050729204757.GP23710@agk.surrey.redhat.com> References: <1119267914.21477.3.camel@dilbert> <1122572640.9888.27.camel@localhost.localdomain> Mime-Version: 1.0 Content-Disposition: inline In-Reply-To: <1122572640.9888.27.camel@localhost.localdomain> 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" Content-Transfer-Encoding: 7bit To: LVM general discussion and development On Thu, Jul 28, 2005 at 01:44:00PM -0400, Ming Zhang wrote: > 1) very hard to solve technically. or > 2) not so easy but doable, just no time and human resource? The hardest part of the fix involves changing the sequence of device-mapper ioctls that LVM2 uses, and that's a couple of weeks' development work, now pencilled into the RHEL4 Update 3 timescale. In the meantime, you can apply the snapshot patches in the -udm tree and use 'dmsetup' manually to activate and deactivate snapshots when lvm2 fails. Patches 8 and 9 at: ftp://sources.redhat.com/pub/dm/patches/2.6-unstable/2.6.12-rc2/2.6.12-rc2-udm1/ (Further patches are needed, but those two plus correct dmsetup use should avoid machine lockups.) Alasdair -- agk@redhat.com