Just a addition to J.Hinchcliffe post.
Since you have both STK 9940B and STK T10000A & B drives I assume you have a ACSLS connect library. You may need to make a media mapping in vm.conf in order to make the previous suggestion to work.
Please look in the
Veritas NetBackup Administrator’s Guide, Volume I page 566 (Media Type Mappings tab).
This is a cut'n paste from the NBU adm volume II
ACS_mediatype:
ACS_mediatype = Media_Manager_mediatype
This configuration entry applies only to NetBackup Enterprise Server
If this entry is used in vm.conf, the ACS media type is mapped to the specified Media Manager media type. You can specify more than one ACS_mediatype entry.
This entry is read and interpreted on the host on which vmcheckxxx and vmupdaterun during a robot inventory operation. Use this entry on every NetBackup media server that functions as an ACS robot control host.
For a list of the valid ACS_mediatype entries, see “Media Type Mappings tab” in the NetBackup Administrator’s Guide for UNIX and Linux, Volume I.