Importing part of vg00

[Jean-Michel Suarez]

Hello,

I'm trying to restore an HP-UX 11i system on another CPU.
With an Ignite-UX tape, I succeeded in restoring everything in the internal hard drive.
Then, I had to let the new system know that there are external disks. Th fact is that these disks also belongs to vg00.
With a vgimport command, it complains that vg00 already exists, of course.
I also tried the vgextend command and get that error message:
Couldn't install the physical volume "dev/desk/c0t8d0".
The path does not specify a valid physical volume.

Anyway, the ioscan -fnkCdisk command shows me the c0t8d0 disk.

So what's wrong ?

[Enrico P.]

Hi,
have you really tried with /dev/desk instead of /dev/dsk?

Enrico.

[Stefan Farrelly]

Use vgscan to identify other disks and what vg they belong to. It will list all available disks and check each one to see which ones belong to the same vg. You can then vgimport those it identifies as belonging to the same vg.

I find it difficult to understand how you could have other disks belonging to vg00 which werent recovered by ignite. This doesnt make sense. Anyway, I would create a new vg and import them there (eg, vg01).

[Jean-Michel Suarez]

Oh sorry,
That was just an error when using keyboard. Of course, that's dsk.

[Robert-Jan Goossens]

Hi,

Think you can import the vg to an other vg.

create vgtemp
import old vg00 to vgtemp
copy data to original vg00.

Hope it helps,

Robert-Jan.

[Jean-Michel Suarez]

Hi Stefan,

In fact, my vg00 is composed about the internal hard drive and 2 externals.
My aim was to be able to make machines substitute each other in case of internal hard drive.
That's why I made an Ignite-UX tape specifying to backup only all the partitions stored on the internal drive.

Now that the restore process worked, I have vg00 composed normally of the internal drive.
But, I have to tell him to also include the other disks !

I also tried a vgscan but it didn't help a lot.
The /etc/lvmtab still doesn't talk about my external drives while ioscan can see them !

[Jean-Michel Suarez]

Robert-Jan,

Can you explain me your answer with a little more details please ?

Thank you

[Robert-Jan Goossens]

Yep,

short one because of my timelimit, if i make an typo ignore it (:-)

you would like to have the abillity to import your data from one server to the other. But vgimport complains about Couldn't install the physical volume "dev/desk/c0t8d0".

How about creating a vgtemp or what ever you would like to name it. Use vgimport to import the disk inside the temp volume group, mount it on /mnt/temp filesystems and copy your data to the excisting logical volumes.

Hope it helps,

Robert-Jan.

[Pete Randall]

Jean-Michel,

It seems to me that you have a problem with the layout of your original system that ought to be straightened out.

It sounds like you have more than just root file systems in vg00 and this is not recommended. VG00 should contain only /, /stand, /var, /usr, /tmp, /opt, and possibly /home. Any non-root data should be kept in separate volume groups. That way you should be able to use Ignite to backup and recover just vg00 and then use conventional backup methods for your data. Restore consists of recovering the O/S (vg00) via Ignite, then using either vgimport (if the VG's are still intact) or your conventional backup to restore your data. This is the way Ignite was designed to function.


Pete

[Jean-Michel Suarez]

Pete,

Is it possible to change my vg architecture in order to reduce the content of vg00 ?

Is that a tricky work or something really easy as that machine is actually on production ?

Thank you

[Robert-Jan Goossens · Accepted solution]

Hi Jean-Michel,

Yes if you have enough free space in the other volume groups you can copy them without a reboot, but not with any users or applications running. You will have to shutdown databases/applications using these logical volumes.

create a new logical volume same size as the one in vg00
create a filesystem on it
mount the filesystem on a tempmount
copy data from vg00 into vg01 in the tempmount
umount /dev/vg00/lvolX
mount /dev/vg01/lvolX on old dir name
change /etc/fstab vg00 into vg01


Robert-Jan.

[Pete Randall]

Jean-Michel,

Sorry for the delay in responding.

As Robert-Jan pointed out, it's relatively simple if you have extra space available.

If not, the process becomes rather involved. You need to backup the non-root file systems to tape, remove the lvols, create a new VG out of the space you've just freed up (the external disks, I hope), create lvols and filesystems within, and then restore your data.

In the future, it will make your life much easier - it's just hard to get where you need to be.


Pete

[Angus Crome]

Once you get all the non-root stuff off, you should check to make sure that no Physical extents are left on the other drives, unless it requires more than the space of one drive. If you want to reduce the number of Physical volumes in vg00, you can look at "pvmove" to get the data moved onto the minimum number of disks.