[linux-lvm] file-based locking initialization failed after pvresize

[Christian Lahti <clahti@gmail.com>]

Hello all:

I have a VMWare virtual CentOS 6 server with the following disk layout:

/dev/sda 15GB
/dev/sdb 100GB

Standard CentOS LVM setup

on sda1
/dev/vg_centos6/lv_root mounted on /
/dev/vg_centos6/lv_swap

on sdb1
/dev/vg_centos6/lv_var mounted on /var

I was starting to run low on disk space for /var, so I shut down the 
machine gracefully, extended the disk in VMWare to 250G and rebooted in 
single user mode. I then ran the following two commands:

pvresize --setphysicalvolumesize 250G /dev/sdb1
lvresize -L250G /dev/vg_centos6/lv_var

I then rebooted expecting the /var to now be 250G instead of 100G. What 
I got was:

No such file or directory trying to open /dev/vg_centos6/lv_var

After dropping to a maintenance shell I could not run any pv* or lv* 
commands, always resulting in the error:

File-based locking initialization failed

After Googling forever I found some lv* and pv* commands take 
--ignorelockingfailure as a parameter, so now I can "see" the pv and lv 
information but I do not know how to recover this partition:

pvdisplay --ignorelockingfailure /dev/sdb1
File-based locking initialization failed
--- Physical volume ---
PV Name /dev/sdb1
VG Name vg_centos6
PV Size 250 GiB / not useable 3.00 MiB
Allocatable yes
PE Size 4.00 MiB
Total PE 63999
Free PE 25599
Allocated PE 38400

lvdisplay --ignorelockingfailure /dev/vg_centos6/lv_var
File-based locking initialization failed
--- Logical volume ---
LV Path /dev/vg_centos6/lv_var
LV Name lv_var
VG Name vg_centos6
LV Write Access read/write
LV Status suspended
# open 0
LV Size 150.00 GiB
Current LE 38400
Segments 1
Allocation inherit
Read ahead sectors auto
- currently set to 256
Block device 253:2

I cannot mount this, I cannot fsck, /dev/mapper/vg_centos6/lv_var does 
not even get created. This is a critical server, can anyone please tell 
me how to reverse this or at least recover the data?

Thanks!

/Christian