Change minor number of vgroot

[Kris Young]

I have a production system running 10.20. I need to change the minor number of vgroot from 0x0a0000 to 0x000000. vgroot has / (lvol1) and /usr (lvol10) on it. Both are hfs. /stand is also on lvol1 in /. Any help would be appreciated.

[Karthik_2]

Kris,
Recreating the volume group may be only option in this case.
Would like to know anyone else has second thoughts about this .
Is there any particular reason you want to change the minor number.

Karthik...

[Karthik_2]

Kris,
You can lookup this link as well...
http://forums.itrc.hp.com/cm/QuestionAnswer/1,1150,0x27ab53921f1ad5118fef0090279cd0f9,00.html
Which indicates ...
You can export the vgroot...and then
boot the system in lvm maintenance mode and recreate the group file and import the volume .
This sounds o.k to me as exporting does not affect the physical volume it just removes the group file and entried in lvmtab .
But I am not sure if one can boot from a already exported root vg through lvm maintenance mode

Karthik...

[Kris Young]

My reason for needing to change the minor number is that I am trying to use Ignite-UX A.3.2. It errors out because the minor number is not 0-9. I cannot use the ?B? version of Ignite-UX, which can handle higher minor numbers, as this system is using OS 10.20 and for now, cannot be upgraded to OS 11.0.

This is a critical system and minimum downtime is crucial. I have listed the following steps and believe I have most of it.

1. boot into lvm maintenance mode
ISL> hpux ?lm

2. Unmount all lvols on vgroot
umount lvol1(/), lvol3(/home), lvol4(/opt), lvol5(/tmp), lvol7(/var), lvol10(/usr)

3. Deactivate old volume group
vgchange ?a n /dev/vgroot

4. Remove volume group entry from /etc/lvmtab
vgexport ?m map /dev/vgroot

5. reboot here? (not sure)

6. Create new volume group
mkdir /dev/vg00
mknod /dev/vg00/group c 64 0x000000

7. Edit vg00 mapfile to change lvol10 (/usr) to lvol6 (/usr)

8. Import volume group info for all disks associated
vgimport ?m map /dev/vg00 /dev/dsk/c?t?d?

9. Activate the new volume group
vgchange ?a y /dev/vg00

10. Backup new volume group config
vgcfgbackup /dev/vg00

11. Check lvols
fsck /dev/vg00/lvol1.......lvol10

12. Mount filesystems on lvols
mount / /usr /var /tmp /opt /home (or mount ?a)

13. Define volumes
lvlnboot ?b lvol1 /dev/vg00 (/ root)
lvlnboot ?r lvol1 /dev/vg00 (/ root)
lvlnboot ?s lvsswap1 /dev/vg00 (swap1)
lvlnboot ?s lvsswap2 /dev/vg00 (swap2)
lvlnboot ?R /dev/vg00

14. rm /etc/mnttab
15. reboot

Thanks in advance for the help!

[Ovidiu D. Raita]

Looks good. I don't think you would have to reboot at step 5: vgroot is not active and you can reimport is as vg00 without problems.

To play safe, I'd try the procedure on another system.

Good luck,
Ovidiu