You may sometimes need to create a disk group that can be imported on a system running an older version of Veritas Volume Manager. You must specify the disk group version when you create the disk group, since you cannot downgrade a disk group version.

For example, the default disk group version for a disk group created on a system running Veritas Volume Manager 5.1SP1 is 160. Such a disk group cannot be imported on a system running Veritas Volume Manager 4.1, as that release only supports up to version 120. Therefore, to create a disk group on a system running Veritas Volume Manager 5.1SP1 that can be imported by a system running Veritas Volume Manager 4.1, the disk group must be created with a version of 120 or less.

To create a disk group with a previous version, specify the -T version option to the vxdg init command.

For example, to create a disk group with version 120 that can be imported by a system running VxVM 4.1, use the following command:

# vxdg -T 120 init newdg newdg01=c0t3d0

This creates a disk group, newdg, which can be imported by Veritas Volume Manager 4.1. Note that while this disk group can be imported on the VxVM 4.1 system, attempts to use features from Veritas Volume Manager 5.0 or later releases will fail.