topic ignite-tape recovery of a mirrored root disk in Operating System - HP-UX

ignite-tape recovery of a mirrored root disk

Kenneth_18 — Sat, 03 Aug 2002 00:38:09 GMT

In our production server, we have all disk mirrored and I made an ignite tape by using make_rovery -Av to include all of vg00.

After some time when we wanted to revert to the back-up copy using the ignite tape, I notice that the mirror copy was not restored. The physical volume was still included in the vg00 after restoration but the logical volumes were not mirrored.

Is this the actual behaviour when igniting a mirrored volume/logical volumes. I tried it on a test server and the r4esults was the same.

Before mirroring the logical volumes again, do I still have to make the physical volume bootable again and other procedures needed for a bootable mirrored root disk?

Does make_recovery or make_tape_recovery also back up the mirrored disk and all of it's contents?

I'm asking this since I want to make a single step recovery tape for the os and application residing on the server which includes entire vg01 and vg02 which are all mirrored.

Re: ignite-tape recovery of a mirrored root disk

Ian Kidd_1 — Sat, 03 Aug 2002 01:01:53 GMT

ignite in itself does not recreate mirrors. It will only back up vg00, and not the mirror. You will have to rebuild the mirrors after recovering from the tape.

HOWEVER, much of this can be automated. You can start make_recovery in preview mode (-p), then modify /var/opt/ignite/recovery/config.recovery.

For a full explanation of how to do this, go to the following link:
http://www.software.hp.com/products/IUX/docs/diskmirror.pdf

It'll also have an example of the config.recovery file.

As for needing to make the mirror bootable - I'm not sure, but I believe you do.

Re: ignite-tape recovery of a mirrored root disk

harry d brown jr — Sat, 03 Aug 2002 01:19:09 GMT

Ignite will not rebuild your mirror.

To answer the question if ignite backs up your mirror, well yes because it is backing up the primary volume vg00 (providing you tell it to back up the entire vg00) therefore it's backing up the mirror.

You should use another backup method to backup vg01 and vg02. If you want to restore your entire system including vg01 and vg02 then you could use ignite to back them up, but you have to be wary of using media that ignite has "certified". I'd be concerned about multiple volumes (tapes), as I've never encountered creating multiple tapes so I'm not sure how ignite will handle making or restoring such.

live free or die
harry

Re: ignite-tape recovery of a mirrored root disk

Donald Kok — Wed, 02 Oct 2002 04:56:46 GMT

Hi Harry,

Ignite just asks for a second tape and contiues.

Greetzz
Donald

Re: ignite-tape recovery of a mirrored root disk

Brian M Rawlings — Wed, 02 Oct 2002 05:21:45 GMT

Ignite does nothing to any disks but the PV used for vg00, so, yes, you have to perform all steps to mirror the boot disk after restoring via your recovery tape.

The man page for make_tape_recovery (successor to make_recovery) clearly states this, but lists how to call a post-exec script once the recovery is complete. Such a script would need to execute all commands needed to fully mirror the root volume, if you wanted the recovery to be completely free of interactive requirements.

I have a rough version of such a script, that would need polishing before you could use it for this purpose. It will at least get you started, but serious disclaimers apply. Use at your own risk, and all that.

Regards, --bmr

Re: ignite-tape recovery of a mirrored root disk

Bernhard Mueller — Wed, 02 Oct 2002 14:32:53 GMT

Kenneth,

in order to include anything beyond the Root VG you have to use make_tape_recovery.

for remirroring the Boot Disk via script you will first have to vgreduce the mirror disk from the Root VG in order to do a pvcreate -B on it to make it bootable. Upon recovery Ignite will include it in the Root VG as a non-bootable disk.

for the other VGs you can just lvextend -m 1 for each Lvol.

Regards
Bernhard