NetBackup provides 3 HCART options (HCART, HCART2, and HCART3). If 4 LTO type drives are being controlled by the same NetBackup Master/Media server (LTO2, LTO3, LTO4, & LTO5). Is there a way to create a fourth drive type? ie: HCART4
Although it makes sense to have hcart4 or hcart5, these media type definitions are not available yet.
In Netbackup, drive can show up in any of the available DriveType(DLT, DLT2, HCART, HCART2, HCART3 etc). There are no HCART4 nor HCART 5 so far but you can always pick and choose one from the above list. As for Netbackup, it does not matter which drive type you chose as it does not affect the capacity nor the performance of the tape drive.