After make_tape_recovery no mirror

[Alex Gobovic]

My first post here: Itanium 11.23 with mirrored LVM (boot-vg00, data-vg01) + vxfs had make_tape_recovery tape created on local tape drive including both vg's. Once itool came up on recovery, options selected were "Advanced Installation" and "Boot from DVD, Recover from tape". Other options were default.
No error messages were reported, only usual messages about creating/extending LV's, making VxFS etc.
On reboot, system came up ok however no mirror is functional, based on lvdisplay and vgdisplay:
--- Physical volumes ---
PV name /dev/dsk/c0t6d0s2
PV Status available
Total PE 4346
Free PE 0
Autoswitch On
Proactive Polling On

PV Name /dev/dsk/c4t6d0
PV Status available
Total PE 4374
Free PE 4374
Autoswitch On
Proactive Polling On

Please note second PV doesn't have s2, and it used to have it before recovery, same on vg01.
I tried vgcfgrestore+vgsync on vg01 (non-boot) to no avail. Also tried idisk -r on the second PV and few other things.

Any idea why it happened and how to make sure mirror works after make_tape_recovery? Thanks

[A. Clay Stephenson]

This is normal and expected behavior. You have to re-mirror vg00 and vgimport non-vg00 VG's after the Ignite recovery. You could script some post-restore recoveries but you should already have a mirror_boot.sh script written so simply run it after Ignite has done its work.

[Steven E. Protter]

Shalom,

I've seen some versions of Ignite preserve mirroring, others ignore it and force you to re-mirror.

swlist -l product | grep -i ignite

Congrats on your first post.

At this point you will need to run a full re-mirror procedure.

Don't forget rx4640, rx3660, rx6600 and other servers feature hardware raid cards which means you don't have to do software raid at all.

SEP

[Alex Gobovic]

Steven, it is Ignite C.6.9.141 on rx8640. Would it do mirroring if I upgrade Ignite to latest version?
I'll first have to fix mirror manually...

[Patrick Wallek]

If you rebuild a system with Ignite, mirroring will be lost.

If a VG, like a data VG, is imported by Ignite, and it is mirrored, then mirroring will be preserved.

I am not aware of any version of Ignite preserving mirroring when rebuilding a system.

[Trevor Roddam_1]

Alex.

This has all been mentioned above but not all together.

Using ignite to recover a volume group will not recover mirroring. This is normal/expected behavior for ignite.

So in your situation, recovering VG00 and VG01 broke all the mirroring. If you had only recovered VG00 and allowed ignite to import VG01, the mirroring in VG00 would be broken; however the mirroring on VG01 would have been preserved.

Generally speaking you have done the right thing in splitting OS and data. Normal practice would be to use ignite on vg00 only and use backups on the other VG's.

vgcfgrestore will not work as the "NEW" VG's have never been mirrored. ignite recreates the OS, not recovering an image like ghost on PC's.

Remember to use pvcreate -B to assign the boot area for the alternate boot HDDs in vg00....and to use lvlnboot -R when finished. Also
There is a guide on mirroring boot disks somewhere...

http://docs.hp.com/en/5991-6481/ch03s04.html#cbddaicd

The integrity option is a bit further down the page.

Believe me when I say this is MUCH easier than older versions of ignite which required using lvm maintenance mode....

You're way ahead of the average admin, you're using ignite.

Trevor.

[Alex Gobovic]

Thanks to all of you, I was able to fix the problem. I was able to find great pdf document on Ignite and MirrorDisk ( 5991-5845.pdf) that also contains sample post recovery procedure/script to help with mirroring. It does only vg00 and only with 2 disks, but it has many great ideas.

Since I experimented a bit too much with vg01 I basically had to blow away lvmtab, recreate it with vgscan, create vg01 from the scratch (mknod, pvcreate, vgcreate, lvcreate, newfs, mount) and restore data.

Restoring vg00 was easier: I just had to do:

vgreduce /dev/vg00
idisk -r

And follow the rest of procedure from mentioned pfd document. Anyway, good disaster recovery exercise BEFORE actual disk failure/disaster!

[Alex Gobovic]

Solution found, closing this thread.