This is a known issue. I have a bug open with IBM who in turn has opened one with SUSE : --------------- This is a short update from SuSE LVL3 folks. his is a short status about the work that has been done to fix this bug. Since the bug has been posted, different SuSE developers have been working on that. They have found a way to track the problem: "by simply deleting and rewriting 200 MB to the first original volume after creating the backups caused corruption on the second original volume." <citat> of one developer I have finally been able to reproduce it, on s390l2. I have set up LVM similar to the setup described in the bug report (three volume groups, several striped volumes on vg01), created two ext3 filesystems (/dev/vg01/lvol[12]), filled them up with several copies of /opt/kde3, then made backups (/dev/vg01/backup[12]) with the filesystems mounted as described above, then mounted those backups read-only. No corruption on any volume so far. After deleting some kde3 copies on /dev/vg01/lvol1 and copying them back again with different names, seemingly random corruption reared its ugly head on _all_ volumes. Try "for i in /mnt/*/? /mnt/*/?? /mnt/*/??? ; do diff -r /opt/ kde3 $i ; done" (ignore the dangling symlinks). /var/log/messages may be worth a look as well. </citat> Afterwards we have contacted IBM Boeblingen, and they have been also able to reproduce the issue in the vanilla LVM-code. Even in version 1.0.7. We tried to reproduce it on x86, but it was not possible, on PPC we do not know yet. Summary: The corruption we see on S/390 can be caused anywhere in the kernel, starting from the memory subsystem to the iobuf on S/390 (suspection of Andrea Arcangeli) to the buffer header code within LVM(suspection of Martin Schwidefsky) to the remapping of blocks within LVM-snapshot specific code paths(and there are many) inside LVM including LV locking issues and list-handling for the exception table which seems to be the instance where the LVM code works out the snapshot-specific block mapping. By next week, you will hear from me; our developers are intensively working on that issue. With kind regards, Thomas Fenton Staff Software Engineer IBM Integrated Technical Services Linux and NUMA-Q support > -----Original Message----- > From: Ihno Krumreich [mailto:ihno@suse.de] > Sent: Thursday, April 15, 2004 5:42 AM > To: linux-lvm@redhat.com; Mauelshagen@redhat.com > Cc: Bernhard Kaindl; Uwe Drechsel; Ulrich Hecht > Subject: Bug when creating snapshots on lvm on s390 > > > Hi, > > we have a filecorruption on a LVM-Volume when a > snapshot is created. This Problem seem to occur only > on s390 (31-Bit mode). > > are there any known issues when using snapshots on lvm on s390? > > regards > > Ihno Krumreich > > How to create the bug: > > - Create three volume groups, which are striped over multiple > physical disks (9 x 2GByte). > - use the second volume group to create a logical volume > - create a file system on this LV (problem occurs with ext2, > ext3, reiserfs) > and put data in the filesystem > - create a snapshot of this LVOL > - the data on the original LVOL are corruptet > > - It is important that the filesystem is mounted read/write > If it is only mounted readonly and the snapshot is > created the corruption does not occur. > > > Machine setup: > > S390 31-Bit with SUSE linux Enterprise Server 8 Service Pack 3 > Machine has 2 Gbyte RAM and 9 Model-3 DASD for the LVM. > > SLES8 has LVM Version 1.0.5 with IBM patches for multipath support. > > To exclude that Kernel modification from SUSE/IBM cause the > problem IBM has testet it with the vanilla kernel 2.4.21 and > LVM Version 1.0.7 and the problem is the same. > > At SUSE we tried to reproduce the problem on x86, but without > success (kernel 2.4.21 with lvm 1.0.5). > > In the attached tar-ball is a file which showes the corruption > starting at byte 0xc000 with a length of 0x1000 Bytes. > > > -- > Best regards/Mit freundlichen Grüßen > > Ihno Krumreich > > "Never trust a computer you can lift." > -- > Ihno Krumreich ihno@suse.de > SuSE Linux AG Projectmanager S390 & zSeries > Maxfeldstr. 5 +49-911-74053-439 > D-90409 Nürnberg http://www.suse.de > > _______________________________________________ > 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/ > _______________________________________________ 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/