From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mikhail Klepachevskyy Subject: Re: Shared snapshots test Date: Wed, 10 Mar 2010 15:34:38 +0200 Message-ID: <20100310133438.GA9704@mick> References: <20100310123713.GA9341@mick> Reply-To: device-mapper development Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: dm-devel-bounces@redhat.com Errors-To: dm-devel-bounces@redhat.com To: dm-devel@redhat.com List-Id: dm-devel.ids Hello! Big thanks! It helped! On Wed, Mar 10, 2010 at 08:11:11AM -0500, Mikulas Patocka wrote: > > You need to suspend and resume the origin device after create message and > before attaching the snapshot. > > > I tried to test multisnapshots but unfortunately got some errors. > > Here is what I did: > > > > # echo 0 `blockdev --getsize /dev/mapper/vg1-lv1` multisnapshot \ > > /dev/mapper/vg1-lv1 /dev/mapper/vg1-lv2 16 0 mikulas 0\ > > | dmsetup create ms > > > > # dmsetup message /dev/mapper/ms 0 create > > dmsetup suspend ms > dmsetup resume ms > > > # echo 0 `blockdev --getsize /dev/mapper/vg1-lv1` multisnap-snap \ > > /dev/mapper/vg1-lv1 0 | dmsetup create ms0 > > > > At this point I got the next error: > > device-mapper: reload ioctl failed: No such file or directory > > Command failed > > > > And these lines appeared in dmesg: > > [ 6876.506623] device-mapper: table: 252:3: multisnap-snap: Snapshot with this id doesn't exist > > [ 6876.506629] device-mapper: ioctl: error adding target to table > > > > Could you check all the steps I performed right and what could cause > > those error messages? > > > > But rather, you could use userspace support for shared snapshots, it makes > the use much easier, you can use lvcreate, lvremove, lvresize commands: > > for lvm-2.02.54: > http://people.redhat.com/mpatocka/patches/userspace/new-snapshots/lvm-2.02.54/ > for lvm-2.02.60: > http://people.redhat.com/mpatocka/patches/userspace/new-snapshots/lvm-2.02.60/ > for lvm-2.02.62: > http://people.redhat.com/msnitzer/patches/multisnap/lvm2/LVM2-2.02.62/ -- Best wishes, Mikhail Klepachevskyy