From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx3.redhat.com (mx3.redhat.com [172.16.48.32]) by int-mx1.corp.redhat.com (8.11.6/8.11.6) with ESMTP id j5TH4lu09840 for ; Wed, 29 Jun 2005 13:04:47 -0400 Received: from postfix1-c.free.fr (postfix1-c.free.fr [213.228.0.79]) by mx3.redhat.com (8.12.11/8.12.11) with ESMTP id j5TH4b5M021531 for ; Wed, 29 Jun 2005 13:04:37 -0400 Received: from postfix3-1.free.fr (postfix3-1.free.fr [213.228.0.44]) by postfix1-c.free.fr (Postfix) with ESMTP id F20D3F19F6C for ; Wed, 29 Jun 2005 18:59:05 +0200 (CEST) Received: from lns-vlq-18f-81-56-213-72.adsl.proxad.net (unknown [81.56.213.72]) by postfix3-1.free.fr (Postfix) with ESMTP id 7DC39173568 for ; Wed, 29 Jun 2005 18:58:58 +0200 (CEST) From: Marc Cousin Subject: Re: [linux-lvm] Issues with md RAID-1, LVM, and snapshots Date: Wed, 29 Jun 2005 19:00:14 +0200 References: <4244A203.2050304@eorbit.net> In-Reply-To: <4244A203.2050304@eorbit.net> MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200506291900.14672.cousinmarc@free.fr> 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" To: LVM general discussion and development I've got exactly the same problem here. Raid1(md)+LVM2 (2.6.11, Xen Domain0), can't snapshot correctly. In dmesg, I've got : attempt to access beyond end of device dm-30: rw=0, want=1905355624, limit=1228800 attempt to access beyond end of device dm-30: rw=0, want=1905357216, limit=1228800 attempt to access beyond end of device dm-30: rw=0, want=8390664, limit=1228800 As soon as I remove the Raid1, the problem disappears. Is it a known problem ? Is there a workaround ? On Saturday 26 March 2005 00:42, Kevin Murphy wrote: > I'm having trouble with snapshot volumes when combining software RAID-1 > with LVM2 striping. > > I have a server with four 18GB drives. I would like to combine them into > two RAID-1 mirrors and then stripe across them with LVM, with the goal > of data redundancy and the ability to make hot backups via snapshots. > > System: > Suse Linux Enterprise Server 9 for x86_64 > kernel 2.6.5-7.147-smp > lvm2-2.00.15-0.8 > > When I set up the drives in one big volume group (no RAID), snapshots > work correctly: > > pvcreate /dev/sdc1 > pvcreate /dev/sdd1 > pvcreate /dev/sdf1 > pvcreate /dev/sde1 > vgcreate -M2 vg1 /dev/sdc1 /dev/sdd1 /dev/sde1 /dev/sdf1 > lvcreate -i4 -I64 -L32G -n lv1 vg1 > mkfs.ext2 /dev/vg1/lv1 > mount /dev/vg1/lv1 /mnt/bigdisk > {put some data in /mnt/bigdisk} > lvcreate -L1G -s -n snap1 /dev/vg1/lv1 > mount /dev/vg1/snap1 /mnt/backup > find /mnt/backup | cpio -ovHnewc > /tmp/backup.cpio > > This works fine. However, if I set up two RAID-1 volumes and stripe > across them with LVM, I get errors when reading from a snapshot: > > mdadm --create -l1 -n2 /dev/sdc1 /dev/sdd1 /dev/md2 > mdadm --create -l1 -n2 /dev/sde1 /dev/sdf1 /dev/md3 > pvcreate /dev/md2 > pvcreate /dev/md3 > vgcreate -M2 vg1 /dev/md2 /dev/md3 > lvcreate -i2 -I64 -L32G -n lv1 vg1 > mkfs.ext2 /dev/vg1/lv1 > mount /dev/vg1/lv1 /mnt/bigdisk > {put some data in /mnt/bigdisk} > lvcreate -L1G -s -n snap1 /dev/vg1/lv1 > mount /dev/vg1/snap1 /mnt/backup > > I get this error: > cpio: Read error at byte 2129920 in file /mnt/backup/file1, padding with > zeros > > dmesg says: > attempt to access beyond end of device > dm-3: rw=0, want=17060337672, limit=67108864 > attempt to access beyond end of device > dm-3: rw=0, want=134226096, limit=67108864 > attempt to access beyond end of device > dm-3: rw=0, want=3499657224, limit=67108864 > attempt to access beyond end of device > dm-3: rw=0, want=3094910976, limit=67108864 > attempt to access beyond end of device > dm-3: rw=0, want=8894171864, limit=67108864 > attempt to access beyond end of device > dm-3: rw=0, want=17060337672, limit=67108864 > > When I extract the archive, file1 is corrupted. > > Is there any special magic that needs to be done with LVM+MD, or have I > hit a bug? > > -- > Kevin Murphy > > > > > _______________________________________________ > linux-lvm mailing list > linux-lvm@redhat.com > https://www.redhat.com/mailman/listinfo/linux-lvm > read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/