topic Re: single stale extent in Operating System - HP-UX

single stale extent

PatBaker — Mon, 08 Oct 2007 13:38:42 GMT

I have a mirrored disk that has a single stale extent but when I try to do a lvsync I get this error.....

root@tfthp02 # lvsync /dev/vg00/lvol3
lvsync: Couldn't re-synchronize stale partitions of the logical volume:
Device offline/Powerfailed

lvsync: Couldn't resynchronize logical volume "/dev/vg00/lvol3".

From what I can find out all the disks are in green light state. It in another part of the country so I can't see it.

Do I need to reboot the machine and try again or is there something else I can try before rebooting?

Thanks.

Re: single stale extent

Patrick Wallek — Mon, 08 Oct 2007 13:49:43 GMT

If lvsync is failing, then chances are very good that you have a bad spot on the disk. The disk may not have failed completely (YET) but chances are good that it is failing.

You should go ahead and schedule time to replace this disk.

Re: single stale extent

Torsten. — Mon, 08 Oct 2007 14:05:38 GMT

See the manual for all steps:

http://docs.hp.com/en/5991-1236/When_Good_Disks_Go_Bad.pdf

Do a "dd" to test the disk.

Re: single stale extent

Tim Nelson — Mon, 08 Oct 2007 17:05:35 GMT

Unless one of the two disks is completely offline, use diskinfo to check. Then you do not know which disk is bad.

dd both disks and see which one gets the io error.

ie. disk 1 "dd if=/dev/rdsk/cxtxdx "of=/dev/null
do the same to the other disk.

With only one bad extent you must at least reduce the mirror before replacing. or at least get all extents to become stale.

I neglected to do this once in a situation where it was the disk that said "current" was bad. Total data corruption..

Re: single stale extent

tkc — Tue, 09 Oct 2007 00:05:44 GMT

normally if you have a stale extent on one disk, there could be a bad block on the other disk having the mirror copy. that could be the reason why your lvsync command failed.

Re: single stale extent

Aneesh Mohan — Tue, 09 Oct 2007 00:43:34 GMT

Hi,

Please do check the disk using pvdisplay ,if the "PV Status" is unavailable then first try to make it available and check the disk using dd ,if its not comming up confirm the disk is bad .

Thanks ,
Aneesh