Fixing a mirrored boot disk

[Jason Martens]

Hey guys,
I have a D330, and the primary boot disk (c0t4d0) is mirrored to a backup boot disk (c0t10d0). Unfortunately, the mirrored lvols are not mirrored in the correct order (ie, the boot partition is not the first partition on the drive). Also, the backup drive doesn't have the correct LIF information on it to make it bootable.

I want to remove the lvols at the beginning of the backup disk, write the LIF information to the disk, then re-mirror the root, boot and swap partitions in the correct order to the backup drive. Will this work? Can I do it without erasing all the other information on the backup drive? Is there anything I am missing here?

Thanks,
Jason

[James R. Ferguson]

Hi Jason:

I'd simply 'lvreduce' (-m 0) each logical volume's mirror; then 'vgreduce' the physical disk in question; and start fresh with a 'pvcreate -B' etc to remirror each logical volume in the correct order. The time to complete this process is relatively short and the liklihood of problems on the primary disk during it very small in my opinion.

...JRF...

[Jason Martens]

Yes, that would be a better option. But there is data on the drive that I don't have mirrored and that I can't move somewhere else. It may be possible to back it up and restore it later, but that would require taking services down, and I don't want to do that if I don't have to.

[James R. Ferguson · Accepted solution]

Hi Jason:

OK. I suggested the approach I did as cookbook. Do this:

# lvreduce -m 0 #...each logical volume
# mkboot /dev/rdsk/cXtYdZ
# mkboot -a "hpux -lq stand/vmunix" /dev/rdsk/cXtYdZ
# lvextend -m 1 #...each logical volume

Regards!

...JRF...

[Shahul]

Hi

U have got the correct answer for JRF...I would like to add one more point.

After all run this command

#lvlnboot -R

Best of luck

Shahul

[Harinath N]

Hi Jason,

A bit from my side..........

First of all you can reduce all the lv's one by one from the mirrored disk. After doing so, you have to do a lvlnboot -R(since alterations had been done on boot, swap and root).
Then you can go ahead for mkboot and lvextending of the filesystems in a normal way and atlast do lvlnboot for boot, dump, swap, root and
onceagain a lvlnboot -R.

But to be on safer side, better ensure a backup of the data in the mirrored disk before starting the activity.

Regards,
N.Harinath