lvmerge backup to original vg00

[Bob Manocchia]

I split my root mirrors prior to a patch install. After the patch install my itanium hpux11.23 system would not boot. I then booted off the uneffected alternate (lvsplit). I now want to re-mirror the backup back to the primary. I know I need to get to LVM Maintenance Mode to do this. My question is can I rename the lvols (lvol1-backup) to lvol1 in LVM Maintenance Mode.

Thanks

[Tim Nelson]

You do not need maintanance mode to remirror.

but if you must.
To boot to lvm maintenance mode.

During boot just after the EFI boots your primary disk you are prompted to hit any key to interupt.

interupt the boot, at the hpux> prompt type in hpux -lm

BTW,

Creating an ignite image before updates is the "best" way to recover from something like this.

Also DRD is now available in 11.23 and 11.31 to clone your root filesystem for testing of updates and recoveries.

but to rename root lvols.. I have not had to do this in a decade or so you better make that Ignite image before you do...

boot to maintenance mode
rename all lvols and rlvols using mv command
check or fix lvlnboot configs

use lvmerge to merge the old to the new ( read the man page as if you do it backwards then you will blow away your good copy ). Another option is just to lvremove your bad lvols and remirror to your good ones.

[Bob Manocchia]

Thanks

After using lvmerge to merge the alternate back to the original I could use vgexport using -m and edit the map file to make the lvols lvol1 instead of lvol1-backup. I would then vgimport vg00 and reboot.

[Tim Nelson]

I do not think you can edit the map file.. but go ahead and try.

just doing a mv is a legitimate way to rename lvols ( although a bit more difficult with vg00 )

if lvlnboot -v says boot, root, swap, and dump are on lvol1, lvol2, etc.. then you should be ok.

I would still create an ignite tape before you do this, if you do not and something gets trashed, then you will have no other way to recover except cold install.


Best of luck, I just have not done the lvplit thing since the 1990's as ignite and now DRD negate any need for it.

[Bob Manocchia]

Thanks. I know about ignite since it goes a ways back. I've been out of touch since we've settled on Red hat as our server OS of choice. What is DRD?

[Tim Nelson · Accepted solution]

Dynamic Root Disk.

Allows you to clone your root disk, apply upgrades or patches on the fly to the cloned copy without touching the currently active root disk.

Then you can boot the copy, check it out, if you are unhappy just boot the orig copy and try again. Or if happy, boot the copy, keep the orig on the side just in case.

Works great, especially for testing patches or updates for full installation or errors without jeopordizing anything.

docs.hp.com

[Bob Manocchia]

Thanks for all the help. I'll go ahead with the lvmerge and rename of the lvols. I'll do some more research on DRD..

[Tim Nelson]

A great way to say thanks is to assign some points ;)

use the pull downs next to each response and pick an appropriate level of worthyness..then click submit at the bottom of the thread.


Have a good one...

T.

[Bob Manocchia]

Sorry. I assigned the points but did not submit them.