Is there a command I can run to rotate and manipulate the tapes on a Sun StorEdge L8?

You can do a

mt offline

to unload a tape.  Not sure if you can get it to load the next tape though.

Tintin has pointed you to the right direstion.

"mt" is the command to play with tapes,

eg:
  rewind tape:
 mt -f /dev/rmt/0n rewind

  forward tape by x EOF mark
  mt -f /dev/rmt/0n fsf x

   mt -f /dev/rmt/0n fsf  offline


man mt
to learn more details

Yes. I know how to use mt to unload tapes and rewind and forward tapes. But for the L8, I need to know how to rotate it, if there is a way. I've heard that some guys have found a way within the solaris commands to rotate the tape drive.

I'll take into account your advice about using "sequential" mode. I don't know if I want to trust freeware on an enterprise system though. I was hoping there was some "backware" loaded into Solaris 9 that few people knew about. I'll keep asking and I still hoping someone knows the answer (if there is one).

Sun StorEdge Enterprise Backup software v. 7.1 (Previously Solstice Backup suite) is expensive, especially when you add the Autoloader control modules - If you didn't buy the software bundled with the L8, you may be able to download the older version, 7.0, for evaluation - but I don't know what charges/licencing/conditions apply for that version.

An alternative would be to find out what the L8 is based on, and see if the original manufacturer has published a programmers guide so you can write your own backup management system - But personally, I'd go for MTX at least for the command-line + programming utilities and maybe write your own database/tape management system.

tfewster's answer worked beautifully. Setting the L8 to sequential mode on, circular mode on, autload mode on and using the mt -r /dev/rmt/0nc rewoffl unloaded the tape and rotated to the next one. Thank yo!!