VxVM Troubleshooting – Increasing the Size of Veritas Disk Private Region

We know that each disk under veritas volume manager is having some identification information in it’s private region, so that the disks are readily identifiable irrespective of the machine they are connected. When we place these disks under Veritas Diskgroups, the VxVM will start writing it’s configuration information to the same tiny private region.
Unfortunately, the size of the private region is set at disk initialization and fixed for the life time of the disk. Whereas the configuration database , that stores volume,plex and subdisks definition will continuously grow based on the configuration change we make. If the private region is too small, then there will be some situations where the private region go full and won’t allow any more configuration database updates in that disk group. And there is no direct solution to increase the priviate region and normally we do follow this offline procedure to increase the private region length
1. Backup All data to tape
2. Re-initialize disks with larger private region
3. Recreate volumes as per the original configuration
4. Restore the data.
And just for an experiment , I have followed the below procedure to increase the private region without bringing the volumes down and the experiment went well. Here is the result of the work I have done
