Almost All Xenserver Logical Volumes Disappeared - Recovery?
- by Alex
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.
edit2
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
