Hi,

Somehow I found my / fs is in ro mode. Hence I'm unable to write anything in it.

Issue started with below message after running lvdisplay, pvdisplay commands.

File-based locking initialisation failed.

Hence I ran below commands on the system, but no luck.


1)

[root@rhel6 dev]# pvcreate --config 'global{locking_type=0}' --uuid TyYai2-HqFJ-6YU1-ugYo-F0pX-dUZg-RBW23q --restorefile /etc/lvm/backup/vg_rhel6 /dev/sda2 vgcfgrestore -f /etc/lvm/archive/vg_rhel6_00000-210568341.vg vg_rhel6
WARNING: Locking disabled. Be careful! This could corrupt your metadata.
Can only set uuid on one volume at once
Run `pvcreate --help' for more information.
[root@rhel6 dev]#



2)

[root@rhel6 etc]# fsck -a
fsck from util-linux-ng 2.17.2
/dev/mapper/vg_rhel6-slashlv: clean, 139540/458752 files, 1486024/1831936 blocks
/dev/sda1: clean, 38/51200 files, 34501/204800 blocks
[root@rhel6 etc]#


3)

[root@rhel6 ~]# pvdisplay --ignorelockingfailure
File-based locking initialisation failed.
--- Physical volume ---
PV Name /dev/sdb1
VG Name newvg
PV Size 34.99 GiB / not usable 4.45 MiB
Allocatable yes
PE Size 4.00 MiB
Total PE 8957
Free PE 7677
Allocated PE 1280
PV UUID Xwg9Q5-gdri-6rDe-VDWt-x2ix-BnBU-xnIpJY

--- Physical volume ---
PV Name /dev/sda2
VG Name vg_rhel6
PV Size 14.80 GiB / not usable 3.00 MiB
Allocatable yes (but full)
PE Size 4.00 MiB
Total PE 3789
Free PE 0
Allocated PE 3789
PV UUID TyYai2-HqFJ-6YU1-ugYo-F0pX-dUZg-RBW23q


4)

[root@rhel6 ~]# mount -o remount,rw /dev/mapper/vg_rhel6-slashlv
mount: cannot remount block device /dev/mapper/vg_rhel6-slashlv read-write, is write-protected
[root@rhel6 ~]#


[root@rhel6 var]#
[root@rhel6 var]# touch abcd
touch: cannot touch `abcd': Read-only file system
[root@rhel6 var]#
[root@rhel6 var]#
[root@rhel6 var]# cd /tmp/
[root@rhel6 tmp]# touch abcd
touch: cannot touch `abcd': Read-only file system
[root@rhel6 tmp]#


can anyone help me to rersolve this issue ASAP?

If the OS (RHEL) finds issues with filesystem (usually due to some hardware problem with the disk or controller) it switches to read only mode to prevent further corruption of the filesystem.

The solution is to:
1) Identify why you're having the issue (e.g. does the server give some indication of disk write issues in /var/log/messages or do you have a front panel led/lcd that gives you some sort of indicator).
2) If you do not have a recent backup of what is on the affected filesystems try to do one ASAP.
3) Repair the issue found in step 1.
3) Reboot into single user mode.
4) Remount the root filesystem as read write in single user mode then run fsck to clear the issues.