We had a hard disc crash of one of two hard discs in a software raid with a LVM on top.
The server is running Citrix xenserver.
On the hard disk which is still intact, the volume group gets detected well, but only one LV is left. (some hashes replaced by "x")
# lvdisplay --- Logical volume --- LV Name /dev/VG_XenStorage-x-x-x-x-408b91acdcae/MGT VG Name VG_XenStorage-x-x-x-x-408b91acdcae LV UUID x-x-x-x-x-x-vQmZ6C LV Write Access read/write LV Status available # open 0 LV Size 4.00 MiB Current LE 1 Segments 1 Allocation inherit Read ahead sectors auto - currently set to 256 Block device 253:0
root@rescue ~ # vgdisplay --- Volume group --- VG Name VG_XenStorage-x-x-x-x-408b91acdcae System ID Format lvm2 Metadata Areas 1 Metadata Sequence No 4 VG Access read/write VG Status resizable MAX LV 0 Cur LV 1 Open LV 0 Max PV 0 Cur PV 1 Act PV 1 VG Size 698.62 GiB PE Size 4.00 MiB Total PE 178848 Alloc PE / Size 1 / 4.00 MiB Free PE / Size 178847 / 698.62 GiB VG UUID x-x-x-x-x-x-53w0kL
I could understand if a full physical volume is lost - but why only the logical volumes?
Is there any explanation for this?
Is there any way to recover the logical volumes?
EDIT We are here in a rescue system. The problem is that the whole server does not boot (GRUB error 22)
What we are trying to do is to access the root filesystem. But everything was in the LVM.
We have only this:
(parted) print Model: ATA SAMSUNG HD753LJ (scsi) Disk /dev/sdb: 750GB Sector size (logical/physical): 512B/512B Partition Table: msdos Number Start End Size Type File system Flags 1 32.3kB 750GB 750GB primary boot, lvm
And this 750GB LVM volume is exactly what we see on top.
Output of vgcfgrestore, but from the rescue system, as there is no root to chroot to.
# vgcfgrestore --list VG_XenStorage-x-b4b0-x-x-408b91acdcae File: /etc/lvm/archive/VG_XenStorage-x-x-x-x-408b91acdcae_00000.vg VG name: VG_XenStorage-x-x-x-x-408b91acdcae Description: Created *before* executing '/sbin/vgscan --ignorelockingfailure --mknodes' Backup Time: Fri Jun 28 23:53:20 2013 File: /etc/lvm/backup/VG_XenStorage-x-x-x-x-408b91acdcae VG name: VG_XenStorage-x-x-x-x-408b91acdcae Description: Created *after* executing '/sbin/vgscan --ignorelockingfailure --mknodes' Backup Time: Fri Jun 28 23:53:20 2013