topic Re: lvmerge error in Operating System - HP-UX

lvmerge error

Guy Humphreys — Fri, 09 Sep 2005 06:19:37 GMT

Hi all,

We have got a failed disk as part of a mirrored LVM set.

the disk that has failed contains lvol7 and 8 in vg00. The failure occured during our backup window and so a variety of other lvms have not merged back. I am lvmerging them now and all have worked so far except for one that lives in vg00. it has merged but the conf data has not written out to /etc/lvmconf/vg00.conf - it has just hung!

commands and output below:

root/jobs $umount /dev/vg00/usersbackup
/root/jobs $lvmerge /dev/vg00/usersbackup /dev/vg00/users
Logical volume "/dev/vg00/usersbackup" has been successfully merged
with logical volume "/dev/vg00/users".
Logical volume "/dev/vg00/usersbackup" has been successfully removed.

**shell is hung - flashing cursor**

Can I kill the lvmerge process?
Do I need to do anything with my vg00.conf file?

I don't want to wipe out the whole of vg00 for obvious reasons!!!

cheers
Guy

Re: lvmerge error

RAC_1 — Fri, 09 Sep 2005 06:27:35 GMT

You can kill lvmerge. but chances are that it
is waiting on i/o and will not be killed.

By any chance, if it gets killed, do vgreduce for that disk, replace (if not hot swappable, you will have to do reboot),
vgcfgrestore on disk and lvmerge.

Re: lvmerge error

Devender Khatana — Fri, 09 Sep 2005 07:40:36 GMT

Hi,

It is clear that the command is waiting for a I/O from the failed disk and will probably never complete unless it is timed out. In this case after waiting for a substiantial time if the process do not come out you can try killing it and removing the lock file /etc/lvmconf//lvm_lock.

HTH,
Devender

Re: lvmerge error

Guy Humphreys — Fri, 09 Sep 2005 10:01:37 GMT

OK, I can kill the lvmerge process after about 10 mins and I have managed to merge most of the other lvms back so at least we have some redundancy.

however, now I am trying to vgreduce the faulty disk and am getting another error.

I broke the mirrors from the disk with lvreduce -m 0 but the lvol8 lvm was not mirrored anyway as it was still in a split state. so I try and lvremove /dev/vg00/lvol8backup and cannot it says device busy. so I do a ps -ef and see this little beastie!

/sbin/fs/hfs/umount /dev/vg00/lvol8backup /backup/var

I try and kill it and nothing, not even a -9 does the job.

So it looks like I need a reboot, my question is how can I check that all my vg00 lvms come up after the reboot. I am not confident that some corruption or other has affected them with all the problems/mucking about that has been done. Can I save the vg00 config anywhere safe to recover from if needed?

thanks as ever guys

Guy

Re: lvmerge error

Devender Khatana — Sat, 10 Sep 2005 00:06:11 GMT

Hi,

You can check using bdf command wheather everything is mounted or not to ensure that all file systems are available.

Also there should not be any problem since your LVOLs have a copy on the good disk which was used for only reading while syncing the faulty disk.

/dev/vg00/vg00.conf should be the file enough to restore vg configuration. You can also recreate it anytime but currently system with a failed disk would probably not do that function as it involves scanning all the disks.

Just see the pvdisplay output of the good disk to ensure you have all the extents in current state and all splitted extents were from the faulty disk only.

#pvdisplay -v /dev/dsk/cxtydz |grep -i stale(Cxtydz is the good disk)

HTH,
Devender

Re: lvmerge error

Guy Humphreys — Mon, 12 Sep 2005 03:30:04 GMT

reboot did the trick, the disk was in a worse state than before, could even read it this time.

did a vgreduce -f
swapped the disk and then remirrored the lvms

cheers all
Guy