topic Re: Replacing a root disk in Operating System - HP-UX

Replacing a root disk

johnh_2 — Mon, 22 Aug 2005 16:29:48 GMT

I had a root disk crash on an old HP-UX 10.20 system. The system is configured with an alternate boot path. I have run the following commands to rebuild the disk and restored the data from backups.

vgchange -a n /dev/vg00
vgexport -v -m /tmp/vg00.map /dev/vg00
pvcreate -B -f /dev/rdsk/c0t6d0
mkboot /dev/rdsk/c0t6d0
mkboot -a "hpux -lq (0;) /stand/vmunix" /dev/rdsk/c0t6d0
mknod /dev/vg00/group c 64 0x000000
vgcfgrestore -n vg00 /dev/rdsk/c0t6d0
vgimport -m /tmp/vg00.map /dev/vg00 /dev/dsk/c0t6d0
vgchange -a y /dev/vg00
lvlnboot -v

When I boot the server and it attempts to boot from the primary path I get the following error:

ISL booting hpux -lq (0;) /stand/vmunix
Boot
: disc(0;0)
Exec failed: Exec format error

I can type hpux at the ISL prompt and continue booting.
ISL> hpux
Boot
: disc(10/0.6.0;0) /stand/vmunix

I have obviously not replaced that many root disks and it's not something I hope to do a lot :) but I would like to get the process documented so I can do it right.
What am I missing?

thanks.

Re: Replacing a root disk

Patrick Wallek — Mon, 22 Aug 2005 16:38:13 GMT

Was the disk mirrored?

Have a look at the LVM chapter of the Software recovery handbook. It has a section on replacing failed disks and should give you a very good procedure.

PDF file here:
http://www1.itrc.hp.com/service/iv/docDisplay.do?docId=prodITRC/DE_SW_UX_swrec_EN_01_E/LVM.pdf

Software Recovery Handbook home:
http://www1.itrc.hp.com/service/iv/node.do?node=prodITRC%2FWW_Start%2FN1%7C16

Re: Replacing a root disk

johnh_2 — Mon, 22 Aug 2005 16:47:53 GMT

No, it was not mirrored.

Re: Replacing a root disk

saju_2 — Mon, 22 Aug 2005 16:51:14 GMT

Hi

Pls refer the link below..

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

it contains the various methods for identifying a disk failure and replacing a failed disk

regards
CS

Re: Replacing a root disk

Torsten. — Mon, 22 Aug 2005 23:57:52 GMT

Hi John,

you mentioned that the disk was not mirrored - so you need to restore your backup. You did mixed 2 procedures too, that one for a new disk and one for replacing. Please refer to the documentation links.

Re: Replacing a root disk

Ermin Borovac — Tue, 23 Aug 2005 00:23:20 GMT

>>> mkboot -a "hpux -lq (0;) /stand/vmunix" /dev/rdsk/c0t6d0

This should simply say

mkboot -a "hpux -lq"

Part in parenthesis (0;) specifies hardware path to the disk device. There is no disk at hardware path 0 thus the failure. man 1m hpux for more information.

Re: Replacing a root disk

Thayanidhi — Tue, 23 Aug 2005 01:32:43 GMT

Hi,
There was a syntax problem! Either you enter simply enter "hpux -lq" or hpux -lq (;0) /stand/vmunix

It is (;0) not (0;)

since you misplaced the ";" the 0 has become hardware path. actually 0 is section.
So(;0) means (hw_path_disk;0)
(0;) means (0;0)

0;0 - there is no such hw path/section!

Actually you can avoid all these.

Regds
TT

Re: Replacing a root disk

johnh_2 — Tue, 23 Aug 2005 11:48:14 GMT

Thank you, Thayanidhi!

I can't believe I missed that syntax error and I can't believe the 2 or 3 of my colleagues missed it either. I guess sometimes you just need a fresh set of eyes to look it over.

Thanks again!