[linux-lvm] Weird corruption of volume group configuration with LVM.

[Hans Engren]

Hi,

After rebooting my system a couple of days ago, I ran into a real strange
problem with the volume group "mw1" I am using.

Doing a vgscan locates no volume groups what so ever.
After doing a `vgcfgrestore -f /etc/lvmconf/mw1.conf -n mw1 /dev/<DISK>`,
I am able to do a `vgchange -a y`, and actually mount /dev/mw1/ftpd.

Doing a vgscan at this point locates no volume groups either.

This means that I can't mount the volume group automatically during
bootup, neither can I use any of the vg* commands in the system. I am just
able to use the volume group as it is, for data storage, without any
possibility to use the LVM features.

I tried to reboot the system, used vgcfgrestore to re-add the
configuration to the disks, and do a vgcfgbackup after that. It produces
the following (with -v):

vgcfgbackup -- finding all volume groups
vgcfgbackup -- volume group found: mw1 
vgcfgbackup -- locking logical volume manager
vgcfgbackup -- checking volume group name "mw1"
vgcfgbackup -- checking existence of volume group "mw1"
vgcfgbackup -- ERROR: volume group "mw1" has an invalid number of physical volumes
vgcfgbackup -- ERROR "vg_cfgbackup(): vg_check_exist" backing up volume group "mw1"

Output from pvscan:
pvscan -- reading all physical volumes (this may take a while...)
pvscan -- inactive PV "/dev/sda"  is in no VG  [4 GB]
pvscan -- inactive PV "/dev/sdb1" of VG "mw1" [3.99 GB / 0 free]
pvscan -- inactive PV "/dev/sdc"  of VG "mw1" [4 GB / 0 free]
pvscan -- inactive PV "/dev/sde"  of VG "mw1" [4 GB / 0 free]
pvscan -- inactive PV "/dev/sdf"  of VG "mw1" [4 GB / 0 free]
pvscan -- inactive PV "/dev/sdg"  of VG "mw1" [4 GB / 0 free]
pvscan -- inactive PV "/dev/sdh"  of VG "mw1" [4 GB / 0 free]
pvscan -- inactive PV "/dev/sdi"  of VG "mw1" [4 GB / 0 free]
pvscan -- inactive PV "/dev/sdj"  of VG "mw1" [4 GB / 0 free]
pvscan -- inactive PV "/dev/sdk"  of VG "mw1" [8.43 GB / 0 free]
pvscan -- inactive PV "/dev/sdl"  of VG "mw1" [4 GB / 0 free]
pvscan -- inactive PV "/dev/sdm"  of VG "mw1" [8.43 GB / 0 free]
pvscan -- inactive PV "/dev/sdn"  of VG "mw1" [4 GB / 0 free]
pvscan -- inactive PV "/dev/sdo"  of VG "mw1" [4 GB / 0 free]
pvscan -- inactive PV "/dev/sdp"  of VG "mw1" [4 GB / 0 free]
pvscan -- inactive PV "/dev/sdq"  of VG "mw1" [4 GB / 0 free]
pvscan -- inactive PV "/dev/sdr"  of VG "mw1" [4 GB / 0 free]
pvscan -- inactive PV "/dev/sds"  of VG "mw1" [4 GB / 0 free]
pvscan -- inactive PV "/dev/sdt"  of VG "mw1" [4 GB / 0 free]
pvscan -- inactive PV "/dev/sdu"  of VG "mw1" [4 GB / 0 free]
pvscan -- inactive PV "/dev/sdv"  of VG "mw1" [4 GB / 0 free]
pvscan -- inactive PV "/dev/sdw"  of VG "mw1" [4 GB / 264 MB free]
pvscan -- inactive PV "/dev/hdb1" of VG "mw1" [57.24 GB / 0 free]
pvscan -- inactive PV "/dev/hdc1" of VG "mw1" [16.11 GB / 0 free]
pvscan -- inactive PV "/dev/hdd1" of VG "mw1" [16.11 GB / 0 free]
pvscan -- total: 25 [186.3 GB] / in use: 24 [182.3 GB] / in no VG: 1 [4 GB]

I hope you see what my problem is, otherwise, tell me what output that
would be needed, and I'll provide it.

Thank you.

 -- Hans.