Extending VG00 onto another disk.

[Brian Ruisi]

This seems like a simple operation, but I hoping someone can shed some light on my problem. I have a server running HPUX 11.0 and it is setup with an internal 18GB drive. I have an external 73GB drive that I want to add to VG00 so that both disks are in the same VG. When I add the second drive to the VG, it limits the usable space to the size of the original drive. Is it possible to add the drive as 73GB and wind up with a VG00 totalling 91GB (relative sizes). It is only possible to add a drive of the same size or smaller to a VG? Is this a product of using SAM, or is it a limitation of the OS? The Extent size it is defaulted to is 4, but this seems OK for the amount of total disk size I am shooting for. I didn't want to have two separate VG's for backup purposes. One VG=one tape.

Thanks in Advance for your help...

[Marco Santerre · Accepted solution]

Unfortunately, your problem is that when vg00 was setup originally, it only had the 18Gig and therefore set the Max_PE of your VG to the limit of the 18Gig. If you want to be able to use your 73Gb, you'll have to define your VG00 at creation with PE_Size and Max_PE enough to be able to use the 73Gb and then add the 18Gb.

So in short, the answer is no. You'll have to Ignite your server using your 73GB as your primary disk in VG00 in order to be able to have a 91 GB Volume Group.

[Ian Lochray]

What is Max PE per PV set to for the volume group? This resticts the maximum number of physical extents on any disk in the VG and could be the cause of your problem. It is set when you create the VG and cannot be changed without recreating the VG.

[Jose Mosquera]

Hi,

Try to keep your vg00 as basic as possible. By doing so you can quickly recover or alter the vg00 configuration using HP's Ignite make_tape_recovery tool. This will leave your application intact on the seperate disk and it is just a matter of running the vgimport command to bring the application back online.

Rgds.

[John Dvorchak]

The others are correct about adding the disk to vg00, it is limited by MAX PE per PV. But you can create a new vg and then include the new vg in the Ignite tape creattion with:
make_tape_recovery -x inc_entire=vgxx

man make_tape_recovery.

Good luck

[Brian Ruisi]

Thanks for the insight. This is a test server, so all in one VG seemed to be acceptable. I had a thought though. Is it possible to make an ignite tape of the current configuration, then restore in advanced mode and set the PE's there? That would save me the reinstall time....

Thanks again everyone for your thoughts.

[Marco Santerre]

Absolutely, as long as when you interact with Ignite, you specify the 73Gb disk as your main disk, and everything else you need to specify for your vg00.

[Brian Ruisi]

When I specify the 73GB drive as the main drive, will it put the OS LV's on the 73 or can I specify the 18GB still? I'm making the backup as we speak.

[Marco Santerre]

It is possible to put your LVs on any disk you want when you use th e interactive Ignite. When you are in to the LVM section, there is a place where you can specify which disk you want to put it on.

[Jeff Schussele]

Hi Brian,

You can specify both disks for vg00 at install, but I believe the first of them in the HW path will be first loaded. So if the 18Gb has a lower HW path number, you should designate only the 73Gb disk & then add the 18 later. It certainly won't need all of 73 to load the OS.

I still would caution you to not create such a large vg00. There's no need for that at all. I'd recommend you just add the 73 as vg01 or whatever & avoid having to Ignite in the first place.
IF you create a new VG with the 73, LVM will poperly size the values, and you *could* even increase the maxPE/PV value to accomodate even larger drives down the road.
Quick, easy, painless...works for me.

Rgds,
Jeff

[Brian Ruisi]

Thanks for the info.
It is more of a can I make it work now. After playing around, I will probably just go with the 2 VG method. If this was a production system, it would be a no brainer.

Thanks again.