Best method for replacing internal vg00 drives?

[Susan Harris]

I have about 14 K servers that I need to replace the 4GB drives that house vg00 to 18GB drives. I have been doing some research and have seen many mentions of using Ignite (which we do have installed on every server). Does anyone have advice on the best way to handle this or another possible, successful option? I know with the Ignite route, I will need to make some changes to expand the 4GB to the 18GB drive...Any info. would be very appreciated.

[Anthony Goonetilleke]

There is a very good article about all the scenarios i.e

Replacing a NON-Boot Disk WITHOUT LVM Mirroring
Replacing a NON-boot Disk WITH LVM Mirroring
Replacing a Root Disk WITHOUT LVM Mirroring
Replacing a Boot Disk WITH LVM Mirroring

Its DocId: KBAN00000347 for both 10.20 and 11 it is a very good read!

[Stefan Farrelly · Accepted solution]

The problem is you have to recreate vg00 as the Max PE's per PV is too small for 18Gb disks (from your current disk size of 4Gb). The only easy quick way to rebuild vg00 is to use ignite to backup vg00, replace the disk, then restore to the new 18Gb drive.
If you dont want to have to insert a tape into each server you can back them up using ignite to an HP server you setup as an ignite server (one with enough free space)using make_net_recovery (instead of make_recovery for tape) and then you can rebuild your servers after the new 18Gb drive is installed by booting from the lan from the ignite server. If your not using 100Mb lan though it will probably be faster to install via tape (unless your 10Mb lan is only lightly used).

[Kofi ARTHIABAH]

Susan:

You are on the right track. Ignite-UX will help you - I would propose the following:

1. If all your servers are on the same segment, you do not need tape drives, however, if they are not, you would have to have a tape drive on each server to boot from.

2. Download Ignite-UX from
http://www.software.hp.com/products/IUX/index.html
and if all your servers are on the same network segment, choose one server to serve as your IUX server (this will hold the images from the other servers) the designated server must have a lot of space (depending on your configuration, each server would require some 200Mb)
The documentation describes how you can create the IUX server and set up clients.
http://docs.hp.com/hpux/pdf/B2355-90677.pdf

3. If you setup the IUX server in the /.rhosts of each of your servers, you can write a script of the form:

for host in `cat /tmp/serverlist`
do
remsh $host "/usr/local/bin/run_ignite"
done

where /usr/local/bin/run_ignite is a script that you create that invokes the make_net_recovery ( the man pages on make_net_recovery has the code that can be used for this script)

4. After the images have been made, you can replace the drives. boot the server and boot from the lan (or from tape drive) Ignite will install on the root disk and create the necessary vg00. If you need to make modifications, you can use the advanced mode.

here is a link of FAQ for more information.
http://www.software.hp.com/products/IUX/docs/iux_faq

hope this helps.

[Timothy Czarnik]

Susan,

My advice? Use the make_recovery tapes. If the ONLY thing on the internal disk is VG00, then this becomes a no brainer. Create the make_recovery tape (to be safe, make 2 per machine in case there are physical tape problems encountered). This can be scripted/cronned to run at night on all these machines. You'll have to visit each machine anyway to physically replace the disks.

Once you have the tapes made (make_recovery -A -C -v -d /dev/rmt/#m), boot from the tape. You can let it run by itself to recreate vg00 exactly the way it was, or interrupt the automatic recovery to resize logical volumes. Either way, its a very easy process. Don't let it become a major project! :) Let the computers do the work... If the disks are 4 GB now, they'll be back up and running in an hour.

-Tim

[Eddie Warren]

Hi Susan,
You are getting quite a few responses. What I wanted to let you know was I agree with Tim to do the "make_recovery" tape. The following is the way I did it when swapping out the 4gb with the 18gb internal drives. I modified the sizes of my file systems to better utilize the larger size drive.

make_recovery -v -A -p

This command builds a config.recover file so you can modify the basic configuration. For example if your new drive is on a new Hardware Path. Or if you need to modify the file system sizes. You will need to have a tape in for this to start, it won't write to it until you tell it to.

make_recovery -r

This resumes creation of the tape after the use of the -p (preview) option. Do not use the -A option at this point, it would recreate the config files.

Once you build the tape you can boot it and allow it to build your new drive. No operator intervention needed. Just make sure when you create the tape to insure the H/W path is the correct one.

Good luck,