topic Re: lost LVM after changed scsi cable's path in Operating System - HP-UX

lost LVM after changed scsi cable's path

emily_3 — Thu, 24 Apr 2008 09:25:14 GMT

Hi,

I have one disk array connected to my server via scsi cable. I unpluged the scsi cable for some maintainment reason. After that I re-plug in the scsi cable and reboot the server but the server couldn't boot up due to missing all the LVM in the disk array.
I guess maybe this is because I have re-plugged to different scsi port. But the problem is that my server has quite a lot of scsi ports, I couldn't remember where is the original scsi port's location. I have tried different location, but still failed.
Can someone help on this. Without change back the original scsi port's location, how can I find my missing lvm? or where can I find the original scsi path? Thanks.

Re: lost LVM after changed scsi cable's path

Torsten. — Thu, 24 Apr 2008 09:44:12 GMT

" I guess maybe this is because I have re-plugged to different scsi port."

You already found the source of the problem...

2 possible solutions:

1) plug the cable back to the original port
2) adjust the LVM config (vgexport/import)

I would prefer 1)

Further steps depend on the system model.
What is it (PA-RISC or Integrity)?

Re: lost LVM after changed scsi cable's path

OFC_EDM — Thu, 24 Apr 2008 11:22:28 GMT

Are you rescanning after moving the ports?
ioscan / insf

If you don't the ctd (/dev/dsk/c1td0 etc) numbers won't change. And you'll never re-connect.

If you have the original ctd numbers and provide the hardware make/model we can probably figure out which port to plug into.

Re: lost LVM after changed scsi cable's path

Torsten. — Thu, 24 Apr 2008 11:26:24 GMT

@ O'Kevin:

How would you run ioscan or anything as long as the server does not boot?

"...the server couldn't boot up due to missing all the LVM..."

But searching methods from the boot prompt are very different for PA_RISC and Integrity - that's why I asked for ...

Re: lost LVM after changed scsi cable's path

emily_3 — Fri, 25 Apr 2008 00:48:37 GMT

Hi,

My server module is PA.
Correct my server couldn't boot up, so I couldn't do any ioscan.
And I tried many different connections, but still couldn't work. I also suspect that even one time I put back to original place, it may still not work....

Thanks very much for your help...

Re: lost LVM after changed scsi cable's path

Torsten. — Fri, 25 Apr 2008 04:11:37 GMT

If you go to the boot menu and look at the configured boot pathes:

Main Menu: Enter command or menu > pa

Primary boot path: intscsib.2
0/0/1/1.2
0/0/01/01.2 (hex)

Alternate boot path: intscsia.2
0/0/2/0.2
0/0/02/0.2 (hex)

and tell us *exactly* the server model and the model of your disk chassis there is a good chance to find the right connector.

Re: lost LVM after changed scsi cable's path

emily_3 — Fri, 25 Apr 2008 05:18:26 GMT

Just remind, my bootable disk is on server itself, not on this lost disk array.

My server is very old L class 9000/800/L3000-7x.

pri-path: 0/0/1/1.2
alt-path: 0.0/2/0.2

Re: lost LVM after changed scsi cable's path

Torsten. — Fri, 25 Apr 2008 05:23:16 GMT

"Just remind ..." - but you did not tell so far ...

Your primary and alternate pathes points to internal disks - you should be able to boot from! Regardless of the external disks.

At least in single user mode.

Try this first and we will see!