LVM

[Marcel Burggraeve]

Ray,

You're absolutely right in saying "My research shows that Mirror-UX must be installed in order to do an lvsplit." BUT to have a mirror in the first place you must have Mirror-UX installed as well.

Personally I wouldn't bother with lvsplit, lvreduce and such but just pull out one of the disks and put it safely away on some shelf.

But if I really had to do something like this I wouldn't even bother to do an upgrade but just pull out one disk and perform a clean install on the other disk(s).
Upgrading a system takes alot of time and effort while the risk of a failure somewhere during the process is huge.
Imho trying to upgrade is a waste of time.

[Wim Rombauts]

Hello Ray,

I once folowed a similar procedure, but I don't think upgrading in this way is a good procedure.

You can indeed use an lvsplit and keep the split LV's as backup top recover your system to the old OS-version. But that still involves a lot of work :
-> Be sure your alternate path points to the disk with the split-off LV's, and confirm with lvlnboot that that disk is bootable.
-> After splitting, mount the /stand filesystem on the split-off disk and edit /stand/bootconf to contain the split-off disk device file.
-> After splitting; mount the / filesystem and edit /etc/fstab to mount filesystems from the split-off LV's.
-> Then, at the time of recovery, you need your recovery media (yes you do !). Boot your system with the recovery media, mount the /stand and / filesystem, reconfigure your LV boot configuration to use the filesystems in the split-off LV's (use lvlnboot to do this). If you do not do this, your system will load it's IPL from the split-off disk, but will then serach for the kernel on the other disk.

Once your system is booted, you need to further recover your root volume group.

Think about another procedure : REDUCE your LV's to only 1 physical disk. REDUCE your VG so hat the second disk is unused.
Set your primary boot path in the boot-console to this second disk.
Boot from your installation CD and do a clean install of HP-UX 11.11 on this second disk.
If you need to copy-over configuration files, activate your 11.00 rout disk with vgchange -a r and copy over anything you want.
If ever your maintenance window is over, you can reboot your system to 11.00 without any further recovery operations. In the next maintenance window, reboot your system with the second disk and you are back at 11.11 and continue working where you stopped.

When you are pleased with your new installation, drop the old 11.00 vg00 volume group and extend the 11.11 vg00 and you have a mrrored configuration.

Clean installs are allways preferred to upgrades.