Procedure for splitting diskgroup to new diskgroup, and downgrading the diskgroup version on the new diskgroup for import to another system running a lower product version,

  • Modified Date:
  • Article ID:000087754


This procedure describes how to split a diskgroup to a new diskgroup and downgrade the diskgroup version of the new diskgroup so it can be imported on a system that supports lower diskgroup version.

Recommend that the new and downgraded disk group be created on the current system (6.0.1) to ensure that the operation is successful and minimizes the chances of errors.  This is especially important during the vxmake process.


This procedure was needed so data from a higher Veritas product version system could be migrated to a system running a lower Veritas product version, i.e., migrate data from a 6.0.1 system to a 5.1 system.


Before the split can be done, check to ensure DGSJ is enabled:

# vxdctl license

If DGSJ is not enabled, switch to the keyless option:

# /opt/VRTS/bin/vxkeyless set SFHENT

# vxdctl license init

Check with:

# vxdctl license

This is the procedure:

Note:   These commands show 'syntax' from our testing here.    Use what suits the environment, i.e., diskgroup names; volume names; disk names; etc..

Disassociate plexes:

# vxplex -g test -f dis vol01-02

# vxplex -g test -f dis vol02-02

Make the disassociated plexes into new volumes:

#  vxmake -g test -U fsgen vol  newvol1 plex=vol01-02

#  vxmake -g test -U fsgen vol  newvol2 plex=vol02-02

 Start the new volumes:

# vxvol -g test start newvol1

# vxvol -g test start newvol2

 Test mount of new volumes:

# mount -F vxfs /dev/vx/dsk/test/newvol1 /test2

# mount -F vxfs /dev/vx/dsk/test/newvol2 /data2

 Umount them:

# umount /test2

# umount /data2

 Umount the original volumes/filesystems:

# umount /<mnt>

 Split the diskgroup:

# vxdg split test newdg disk5 disk6

Note:  uses the disks for the new-volumes in above command.


# vxprint -htg newdg

# vxprint -htg olddg

 Now for downgrading the newdg version.

First make config copies of newdg:

# vxprint -mpvshrg newdg > vxprint.1

# vxprint -htg newdg > vxprint.2

Destroy newdg:

Note: If they are mounted need to umount first.

# vxdg destroy newdg

 Now make new ‘newdg’ with lower version:

# vxdg -T 150 init newdg  disk5=emc_clariion0_4 disk6=emc_clariion0_5

>>Use same disk and disknames that were used before!!

 Check version:

# vxdg list newdg

… should show version 150

Now recover the data from the vxprint.1:

# vxmake -g newdg -U fsgen -d /vxprint.1

 Check vxprint output:

# vxprint –htg newdg

 Start the volumes:

# vxvol –g newdg start newvol1

# vxvol –g newdg start newvol2

 Mount them

# mount -F vxfs /dev/vx/dsk/newdg/newvol1 /test2

# mount -F vxfs /dev/vx/dsk/newdg/newvol2 /data2

 Check the data

If all looks good now ready to transfer the newdg to the 5.1 system.

 Umount to deport to 5.1 system

# umount /test2

# umount /data2

 Deport from 6.0.1 system:

# vxdg deport newdg

 Import on 5.1 system:

# vxdg import newdg

# vxvol –g newdg startall


# mount -F vxfs /dev/vx/dsk/newdg/newvol1 /test2

# mount -F vxfs /dev/vx/dsk/newdg/newvol2 /data2

 When finished, reset vxkeyless.

# /opt/VRTS/bin/vxkeyless set NONE



Terms of use for this information are found in Legal Notices.



Did this article answer your question or resolve your issue?


Did this article save you the trouble of contacting technical support?


How can we make this article more helpful?

Email Address (Optional)