vg's for Disaster recovery

[khilari]

Hi guys, i wanted to ask that in a DR situation should we just take the vg00 image in the tape recovery or should we add all the vg's in the tape.
The other thing is that in the ignite tape what info is stored of the vg's. Will it just specify what we get when we do a vgdisplay or does it contain data also for the additional vg's. i am just concerned because my DDStape is only 24gb. And the additional vg's other than vg00 comprise of 320gb.
Thanks

[James R. Ferguson]

Hi:

An Ignite tape should be *only* for vg00.

In a disaster recovery exercise (or real disaster) you would recover your vg00 using your Ignite tape. You would then create ('pvcreate, 'vgcreate', 'lvcreate' and 'newfs') the LVM structures and filesystems you need other than those contained in vg00 and restore your data from backup tapes to them.

Keeping 'vg00' devoid of everything but the standard operating system logical volumes makes operating system upgrades easy. So too does keeping an Ignite tape devoid of everything outside of 'vg00' make disaster recovery easy.

Regards!

...JRF...

[DCE]

In a Dr scenario you will rstore vg00 from Ignite.

Then you rebuild the rest of the VG's and lvol's on the external disks with vgvreate and lvcreate.

Once the lvols have been created, then you use the restore command of whatever application you used to back up the external vg's to restore the data to external disks.

You will need documentation to recreate the vg's and lvol's. I would suggestion a weekly run of the sysinfo program, with the output stored in root's home directory. That way the info is backed up via Ignite, and will be available after the ignite restore at the DR site.

[Sundar_7]

Ignite tape is meant for only OS recovery. You should have a better mechanism for restoring the non-vg00 data and not rely on the ignite tape.

By default make_tape_recovery will only concern with VG00. But you could use the -x option to include data of other VGs as well (though I believe it is not a very good idea).

Ignite tape will contain the map file for the Volume groups but will most likely not be able to import the volume groups in the DR machine since the physical volumes are going to be different. Also the LVM headers should be in place in the PVs that the DR machine sees.

A better approach would be to take the ignite for VG00 and restore to the DR machine. Script the creation of the volume groups and the filesystems. Create the LVM layout in the DR machine and restore the data.

Sundar.

[A. Clay Stephenson]

You DR should be a two-phase operation.

1) Create a bootable machine that is fully patched, correctly tuned, and has all the base software installed and configured. An Ignite image of /dev/vg00 is sufficient for that. This phase should also restore your normal commercial backup system (if applicable) during this phase. This means, for example, if you are using Data Protector and /var/opt/omni is not in /dev/vg00 then your make_tape_recovery should include the VG that houses /var/opt/omni. The idea for this phase is to get the OS installed, patched, and your main backup software up and running BUT to keep your Ignite image as lean and mean as possible. You should also have stored images of bdf outputs, LVM and/or VxVM configurations, and any other critical system information you might need stored in textfiles. For example, I have scripts generated automatically each week that will recreate all the non-vg00 VG's and collect all needed system restoration data in a file.

2) The remainder of your applications and data should be restored using your conventional backup and restore tools. (Data Protector, Netbackup, frecover, tar, cpio, pax, vxdump, et al)

[gbruner]

I have a couple of questions to add to this discussion. The first one expands on khilari's original question: 'what to include on recovery tape'.
I create recovery images of all servers onto my ignite server. I use 'make_tape_recovery' to make recovery image of ignite server. The question is: Do I need to include recovery images of the other servers in the ignite server recovery tape?
The second question is for A. Clay Stephenson: Could you please attach some of the scripting you have mentioned which automates archival of DRP recovery information?