Known catalog backup limitation
Veritas supports mixed versions of NetBackup in the backup environment. Limitations exist, however, when you back up the NetBackup catalog.
If the master server performs catalog backups to a separate media server, the media server must use the same version of NetBackup as the master server. Failure to use the same version of NetBackup on the media server results in improperly protected catalog data.
Since the NetBackup catalog resides on the master server, the master server is considered to be the client for a catalog backup. If the NetBackup configuration includes a media server, it must use the same NetBackup version as the master server to perform a catalog backup.
More information on mixed version support is available.