Creating snapshots of logical volumes belonging to a clustered volume group is not currently possible, which means there is no reliable way to create a consistent backup of data on one of these logical volumes. Creation of snapshots based on clustered logical volumes that were activated exclusively (lvchange -aey) should theoretically be possible since only one node has access to that logical volume, however since the exclusive state is a property of the activation and is not stored in metadata, there would need to be additional checks to allow for creating a snapshot of a clustered lv if that property is present.
upstream in version 2.02.83
Fixed in lvm2-2.02.84-1.el5
We need to turn on snap of mirrors if this is going to be a back port of the RHEL6.1 version of this bug. Otherwise we need to state that exclusive cmirror snaps are not supported. "Snapshots and mirrors may not yet be mixed."
Does it give a sensible message? I don't think we will port snaps of mirrors in rhel5. A note will be needed.
It does give a sensible message. So, I'll add the "needs tech notes" flag based on comment #12 and mark this feature verified for linear and stripe volumes only. [root@grant-02 ~]# lvchange -aye grant/linear grant/stripe grant/mirror [root@grant-02 ~]# lvs -a -o +devices LV VG Attr LSize Origin Snap% Log Copy% Devices linear grant -wi-a- 100.00M /dev/sdb1(0) mirror grant mwi-a- 100.00M mirror_mlog 100.00 mirror_mimage_0(0),mirror_mimage_1(0) [mirror_mimage_0] grant iwi-ao 100.00M /dev/sdb1(38) [mirror_mimage_1] grant iwi-ao 100.00M /dev/sdb2(13) [mirror_mlog] grant lwi-ao 4.00M /dev/sdc3(0) stripe grant -wi-a- 104.00M /dev/sdb1(25),/dev/sdb2(0) # CLUSTER LINEAR WORKS [root@grant-02 ~]# lvcreate -n snap1 -L 50M -s grant/linear Rounding up size to full physical extent 52.00 MB Logical volume "snap1" created # CLUSTER STRIPE WORKS [root@grant-02 ~]# lvcreate -n snap2 -L 50M -s grant/stripe Rounding up size to full physical extent 52.00 MB Logical volume "snap2" created # CLUSTER MIRROR DOES NOT WORK [root@grant-02 ~]# lvcreate -n snap3 -L 50M -s grant/mirror Rounding up size to full physical extent 52.00 MB Snapshots and mirrors may not yet be mixed. [root@grant-02 ~]# lvs -a -o +devices LV VG Attr LSize Origin Snap% Log Copy% Devices linear grant owi-a- 100.00M /dev/sdb1(0) mirror grant mwi-a- 100.00M mirror_mlog 100.00 mirror_mimage_0(0),mirror_mimage_1(0) [mirror_mimage_0] grant iwi-ao 100.00M /dev/sdb1(38) [mirror_mimage_1] grant iwi-ao 100.00M /dev/sdb2(13) [mirror_mlog] grant lwi-ao 4.00M /dev/sdc3(0) snap1 grant swi-a- 52.00M linear 0.02 /dev/sdb1(63) snap2 grant swi-a- 52.00M stripe 0.02 /dev/sdb1(76) stripe grant owi-a- 104.00M /dev/sdb1(25),/dev/sdb2(0)
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An advisory has been issued which should help the problem described in this bug report. This report is therefore being closed with a resolution of ERRATA. For more information on therefore solution and/or where to find the updated files, please follow the link below. You may reopen this bug report if the solution does not work for you. http://rhn.redhat.com/errata/RHBA-2011-0986.html