topic Re: Adding root disk to the system in Operating System - HP-UX

Adding root disk to the system

Andrey_34 — Thu, 08 Feb 2001 14:27:08 GMT

Hi,
here is some kind of How-To.
A month ago, we had a disk with the system installed on it. Then, after installing some patches and then removing them, system was crashed. It is impossible to boot from this disk (From ISL : hpux -XXX - all options doesn't worked) Several days after disaster, system was installed onto another disk. Someone told me, that the good way to follow is using Recovery Shell from support disk.

So, is it possible to add LVM structure from first disk (where system was crashed) to the second disk?

Re: Adding root disk to the system

John Palmer — Thu, 08 Feb 2001 15:47:28 GMT

Yes, you can import the LVM structure from the old vg00 as follows:-

1. Choose a name for the volume group for example vgoldroot.
2. mkdir /dev/vgoldroot; cd /dev/vgoldroot
3. mknod group c 64 0x??0000
ensure that ?? is a unique number, do
ls -l /dev/*/group to check
4. vgimport vgoldroot /dev/dsk/c?d?t?
where c?d?t? is your old boot disk.
5. Activate the volume group.
vgchange -a y vgoldroot

You will now be able to access the old logical volumes, for example:

mkdir oldroot
mount /dev/vgoldroot/lvol3 /oldroot

Hope this helps.

Regards,
John

Re: Adding root disk to the system

Sandor Horvath_2 — Thu, 08 Feb 2001 16:01:45 GMT

Hi !
Jhon has right only one other think>
first check vgimport possibility in old disk with:
vgscan -a -p

regards, Saa

Re: Adding root disk to the system

Ajitkumar Rane — Thu, 08 Feb 2001 16:59:19 GMT

One more addition after you import the old root disk. You can do vgdisplay so you can get all the logical vols on the disk in case you plan to mount partitions then root, but you might have to guess which partion is what after mounting or match it with the current rootdisk mount points.

Also are you talking about (adding)copying the lvm structures from the old disk to the new root disk? like we do a vgcfgrestore to copy the lvm structures to a replaced disk, so you get the partitions as they where on the failed disk.
In the case of primary root disk, It wont be possible.

Good luck.