mirroring problem

[Johnny Pate]

I have a k420 at HP-UX 11. At one point all the logical volumes on VG00 were mirrored with strict allocation between disks. For some reason, I lost all mirroring on vg00.
Two of the logical volumes (var and usr) are spread
out between the two disks. Is there anyway I can get all the data on one disk so I can setup mirroring with strict allocation. Of course the caveat being, without down time. Thanks

Johnny

[Peter Brimacombe]

you are definitely in over your head

You need to hire someone with knowledge and experience in logical volume management and MirrorDisk.

but there are three options

I would first see if all of vg00 would fit on one disk
it's better to do a make_tape_recovery for just one disk
then you would do a make_tape_recovery of the system just the way it is now - specify the interactive option, then boot from the tape go to the advanced option and reconfigure vg00 interactively, the system will install itself on the first disk, then for each logical volume in vg00 add the mirror extent from the other disk - figure that the system will be down 8 hours

if there isn't space then buy two bigger disks , then do a make_tape_recovery, pull out the old disk drives and shove in the new disks and install the old operating system - again figure the system will be down 8 hours

door number three - buy a new system with bigger disks - once it is working then shutdown the old system - this could be done with no downtime

[Michael Tully]

Hi Johnny,

It's looks like you've inherited a turkey.
The best and only method that you don't have
to spend megabucks on is to install a set of
fresh disks and boot off an ignite tape.
You *will* need downtime to do this task.
It is possible to do this with the assistance
of either the response centre or here in
the forums but would need a fool-proof plan
to start with. If you are not confident in
doing this task, get the appropriate help.

Michael

[Denver Osborn]

Hi Johnny,

Could you provide some more information?

What does lvdisplay show for /var and /usr. Are the mirrored copies 0 or 1? I'm assuming there are 2 disks involved and they're the same size. With that said, does pvdisplay show free extents for either of the disks in VG00? If there are free extents on your primary, you might be able to use pvmove to move the /var and /usr extents from one disk to the other. That's only if there's enough space to allocate with the destination pv... Then if pvmove can be done, you'd then be able to lvchange the allocation policy to strict and create your mirrored copies. Although I've got a feeling we're not going to be able to do any of this. Chances are, someone turned off strict allocation (and reduced the mirrored copy) because they needed more space for /usr and /var.

Regards,
-denver

[Martin Johnson]

You could use pvmove to the extents around. However, you may need to add another disk to the volume group.


Marty

[Martin Johnson]

I forgot to mention that pvmove (man pvmove) will not cause down time, but if the disk is busy it may take a long time to execute.


Marty