From: Christoph Peus <cp@uni-wh.de>
Date: Wed, 12 Jul 2006 11:05:34 +0200
Message-ID: <e92e0t$uit$1@sea.gmane.org>
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Subject: [linux-lvm] Cannot create more than one snapshot per origin
Reply-To: LVM general discussion and development <linux-lvm@redhat.com>
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To: linux-lvm@redhat.com

Hi,

when I try to create more than one snapshot of the same origin, the 
second and following snapshots are marked "inactive" and report 
Input/output errors all the time:

Berfore the first snapshot:

lunkwill pri # lvscan
   ACTIVE            '/dev/export/lvol0' [1.34 TB] inherit
   ACTIVE            '/dev/export/lvol1' [800.00 GB] inherit

lunkwill pri # lvcreate -s -L20G -n test /dev/export/lvol0
   Logical volume "test" created
lunkwill pri # lvscan
   ACTIVE   Original '/dev/export/lvol0' [1.34 TB] inherit
   ACTIVE            '/dev/export/lvol1' [800.00 GB] inherit
   ACTIVE   Snapshot '/dev/export/test' [20.00 GB] inherit

Everything's fine so far. Now the trouble starts:


lunkwill pri # lvcreate -s -L20G -n test2 /dev/export/lvol0
   Logical volume "test2" created
lunkwill pri # lvscan
   /dev/export/test2: read failed after 0 of 4096 at 1473844805632: 
Input/output error
   /dev/export/test2: read failed after 0 of 4096 at 0: Input/output error
   inactive Original '/dev/export/lvol0' [1.34 TB] inherit
   ACTIVE            '/dev/export/lvol1' [800.00 GB] inherit
   ACTIVE   Snapshot '/dev/export/test' [20.00 GB] inherit
   inactive Snapshot '/dev/export/test2' [20.00 GB] inherit


I'm using an xfs filesystem on /dev/export/lvol0 and the following 
software versions:

kernel: vanilla 2.6.15.1
device-mapper: 1.02.07
lvm2: 2.02.05


Thanks for your help in advance!

Regards
Christoph