topic Split mirrored VXVM disk to use as boot disk in Operating System - HP-UX

Split mirrored VXVM disk to use as boot disk

Mac86 — Wed, 16 Jun 2010 16:20:32 GMT

I have added a disk to my rp3440 and mirrored the rootdg.
rootdg has 3 disks in the mirror now.
I would lkie to split one out to use as a boot disk on another system.

What commands should I use??

in vxdiskadm - there is the option for removing a failed disk.
Should I use that??
Will the disk be intact - VXVM bootable ??

Thanks

Re: Split mirrored VXVM disk to use as boot disk

Emil Velez — Wed, 16 Jun 2010 23:04:32 GMT

why not just make a net recovery image of the current system on a ignite server then just restore the ignite image to a different system changing the hostname and IP. That would be a proper way to create another sysetm with its own hardware the same as another system.

if you remove the mirored disk you do not have any protection from a disk failure.

Re: Split mirrored VXVM disk to use as boot disk

Mac86 — Thu, 17 Jun 2010 13:38:25 GMT

Emil, the other system is across the country and not accessible from this plant.

There are 3 disks that are part of the mirror, I will removing only one of them and then remirroring on the new system.

Mike

Re: Split mirrored VXVM disk to use as boot disk

Prashanth.D.S — Fri, 18 Jun 2010 02:49:24 GMT

Hi Mac,

The vxbrk_bootmir script can be used to automatically split the VxVM boot mirror and convert it to an independent diskgroup.

For example :

#/etc/vx/bin/vxbrk_rootmir -g test_rootdg -vb c0t1d0

Check if this script is available on your system else contact your HP Support team to get one.

Best Regards,
Prashanth

Re: Split mirrored VXVM disk to use as boot disk

Raj D. — Fri, 18 Jun 2010 04:04:49 GMT

Mac86,

It would be nice to look at the
#vxprint -hrt output first:
However assuming default configuration you can check this out:

- Suppose you have two disk rootdisk01 & rootdisk02 in rootdg mirrired, you can break with the below steps:

1. Break mirrir for rootdisk02. rootdisk02 can be used for other purpose.

# for i in `vxprint -g rootdg -hrt | grep ^pl | awk '{print $3}' | uniq`
> do
> echo "VOL=$i "
> vxassist -g rootdg remove mirror $i !rootdisk02
> done
VOL=optvol
VOL=rootvol
VOL=standvol
VOL=swapvol
VOL=tmpvol
VOL=usersvol
VOL=usrvol
VOL=varvol
#

2.Remove the Alternate disk from diskgroup.
# vxdg -g rootdg rmdisk rootdisk02

3. Verify the plexes from rootdisk02 are not listed:
# vxprint -g rootdg -hrt

4. Reboote and check booting off the ALT disk by interupting at PDC or EFI, and choose alternate disk. It might throw an error due to two rootdg disk, but it will boot up eventually.

Cheers,
Raj.