logical volume not mounting

[sudhir_3]

Dear all
I have hp workstation running hp-ux 10.2 of applo 700 series. one logical volume not getting mounted. If I check through sam the disk where logical volume was is showing unused.(volume group within this disk is also not seen) what to do to get back the volume group and logical volume of disk.
volume group information is there in fstab and lvmtab.
if I do vgchange to activate the volume group it gives error I/O error while reading VGDA.

Thanks
sudhir

[Frederic Sevestre]

Hi,

I am afraid you have a hardware problem.
What is about the ioscan and diskinfo ?

#ioscan -fnC disk

# diskinfo /dev/rdsk/cxtydz

Fr??d??ric

[Paula J Frazer-Campbell]

Hi

A Volume group will not get mounted if it fails the fsck on boot.

What does dmesg tell you?

Try a reboot and pay attention to error messages.

I had this occur recently and I am afraid it was a failed disk.

I hope you have good backups.

HTH

paula

[James R. Ferguson]

Hi:

See if you can obtain information about the associated physical disk from 'diskinfo':

# diskinfo -v /dev/rdsk/cXtYdZ

If you don't get a good physical size, or you get "diskinfo can't open..." then I suspect you have a faulty disk.

Regards!

...JRF...

[Martin Burnett_2]

Hello,

Check to see if you have a file called /etc/lvmconf/vgXX.conf where the vgXX is replaced by the actual volume group name of the logical volume. If it exists do the following:

# strings /etc/lvmconf/vgXX.conf

Does the disk(s) assigned to that volume group show up correctly in this file? If so you can do the following:

# vgcfgrestore /dev/vgXX /dev/rdsk/cXtXdX

where cXtXdX is replaced by the actual disk device file (i.e. c0t6d0).

This will restore the VGDA/VGRA on the disk from the vgXX.conf file and should restore LVM access to the disk.

Thanks for participating in the forums,

Martin
Chaos reigns within. Reflect, repent, and reboot. Order shall return.

[Bill McNAMARA_1]

does sound like one of failed disk:
verified from
ioscan -fnkC disk
response

or data corruption on the disk header caused by dd /pvcreate -f operation or equivalent.

Headers restored via vgcfgrestore as mentioned, which will allow vg activation.

strings /etc/lvmtab to determine which VG the PV should be in. The LV to VG mapping should be determined by the failed mount (cat /etc/fstab)

If the disk is not failed and vgcfgrestore succeeds, after restoring the header, which will restore from /etc/lvmconf/ information, (assuming /dev/vgXY/* still exists), there is no guarentee that the lv will mount. The data could have been corrupted by a dd.. but at least the disk will be ready for newfs/restore.

Later,
Bill

[PIYUSH D. PATEL]

Hi Sudhir,

I think that you may be having a disk problem. Find out after booting that what exact errors are comming and check the dmesg also.

use diskinfo /dev/rdsk/c*t*d*

also do a
dd if=/dev/rdsk/c*t*d* of=/dev/null bs=512

This command will check if the idsk is having problems ( bad sectors etc.)

check strings /etc/lvmtab and find out if that disk exists in that vg.

HTH,
Piyush