Very Computer

Hello there:

I posted this e-mail one more time in the past.  But, unfortunately my mail got erased.  So, I am reposting it.  Your input would be highly appreciated.

I ran DD to replicate two PVs.
After reconfiguring with CFGMGR, I see duplicated PVID on both source and targetPVs.
Now, my source is currently mounted to the system.  So, when I VARYOFFVG and EXPORTVG and IMPORTVG it, I see both soure and target having the same VG and PVID.
Therefore, I can't mount both PVs (or its LVs) to the filesystem simultaneously.

Now, what do I have to do (like changin ODM/VGDA), so that I can mount both soure and target with diffent VG and PVID number to the same system.  

Thanx a bunch.  Happy holidays ...

- Sheik

Hello there:

I have posted this message couple of days ago.  But, for some reason, my message got deleted.  So, I am reposting it.  Your input will be appreciated.

Happy holidays ...

- Sheik

You can change the PVID when the VG is exported using "chdev -l hdiskX -a pv=clear; chdev -l hdiskX -a pv=yes", but there is no way to change the VGID on the disk.
Changing it in the ODM database will just make it out of sync with the disk.

If I were you, I'd start over. Create a new VG and use cplv to copy all of the logical volumes to the new VG, then edit the /etc/filesystems file to create mount
points for the filesystems using the new LV names that will be assigned.

If you have no need to keep both VGs around, you might do just as well making a backup of the data, replacing the disks, remaking the VG and filesystems, then
restoring the data. If you need help with that, check out either Storix, savevg (AIX command) or Sysback.

----------------------------------------------
Anthony Johnson         1-619-291-4500
Storix Software         1-619-291-4590 (fax)

Here was my last response to this question.  I have done this kind of
thing (although not supported by IBM).  Once the PVID is changed, you
will have to reimport the copy VG with a different name.  There will
be duplicate LV names so the LV names on the copy VG will be changed
as it is being imported.  You can use chlv to change them to something
more descriptive if you want.  You will then need to update the
/etc/filesystems to point a NEW directory to the NEWLY named LVs so
BOTH filesystems can be mounted at the same time (with different
directories).

----------------------- OLD POST ------------------------------------
You could write a new PVID to the hdisk and write a new PVID to the
VGDA on the second drive. Then you should be able to import the VG under
a different name.  I was able to do this by dd'ing about 4MB off of the
PV in question.  Then using a binary editor like bvi to find and replace
the PVID's within that image.  I then re-dd'd the changed image back onto
the disk, rmdev -dl hdiskX to clear the old PVID information out of odm,
cfgmgr, and import the copied VG on it's disk with the hand created PVID.

I have no idea if this will mess anything else up, or any other
dangers/issues
in doing this, but I was able to move a testvg/disk to a new PVID by
using this method.

 - Matt
--
_______________________________________________________________________

   << Comments, views, and opinions are mine alone, not IBM's. >>

I can't use other means of backup/recovery, since our product handles it.  

Your input will be appreciated.  

Happy holidays ...

- Sheik

: You can change the PVID when the VG is exported using "chdev -l hdiskX -a pv=clear; chdev -l hdiskX -a pv=yes", but there is no way to change the VGID on the disk.
: Changing it in the ODM database will just make it out of sync with the disk.

: If I were you, I'd start over. Create a new VG and use cplv to copy all of the logical volumes to the new VG, then edit the /etc/filesystems file to create mount
: points for the filesystems using the new LV names that will be assigned.

: If you have no need to keep both VGs around, you might do just as well making a backup of the data, replacing the disks, remaking the VG and filesystems, then
: restoring the data. If you need help with that, check out either Storix, savevg (AIX command) or Sysback.

: > Hello there:
: >
: > I posted this e-mail one more time in the past.  But, unfortunately my mail got erased.  So, I am reposting it.  Your input would be highly appreciated.
: >
: > I ran DD to replicate two PVs.
: > After reconfiguring with CFGMGR, I see duplicated PVID on both source and targetPVs.
: > Now, my source is currently mounted to the system.  So, when I VARYOFFVG and EXPORTVG and IMPORTVG it, I see both soure and target having the same VG and PVID.
: > Therefore, I can't mount both PVs (or its LVs) to the filesystem simultaneously.
: >
: > Now, what do I have to do (like changin ODM/VGDA), so that I can mount both soure and target with diffent VG and PVID number to the same system.
: >
: > Thanx a bunch.  Happy holidays ...
: >
: > - Sheik

: ----------------------------------------------
: Anthony Johnson         1-619-291-4500
: Storix Software         1-619-291-4590 (fax)

Clearly your product doesn't handle it. I don't know what VTOC is but you just can't copy an entire disk or volume group and expect to be able to import it along with the original. As I mentioned, you can change the PVID on a disk but not the VGID, and you cannot have two volume groups active at the same time using the same VGID. You also cannot have duplicate LV names in two different
volume groups imported at the same time.