Loading and unloading tapes

6.10 LPAR mode z/VM guest

Unload tapes with the mt command. How to load tapes depends on the stacker mode of your tape hardware.

Procedure

Unload tapes with a command of this form: 
# mt -f <node> unload
where <node> can be a device node for the non-rewinding device or for the rewinding device.
Whether you can load tapes from your Linux® instance depends on the stacker mode of your tape hardware. There are three possible modes:
manual
Tapes must always be loaded manually by an operator. You can use the tape390_display command to display a short message on the tape device's display unit when a new tape is required.
automatic
If there is another tape present in the stacker, the tape device automatically loads a new tape when the current tape is expelled. You can load a new tape from Linux by expelling the current tape with the mt command.
system
The tape device loads a tape when instructed from the operating system. From Linux, you can load a tape with the tape390_display command. You cannot use the mt command to load a tape.

Example

To expel a tape from a tape device that can be accessed through a device node /dev/ntibm0, issue: 
# mt -f /dev/ntibm0 unload
Assuming that the stacker mode of the tape device is system and that a tape is present in the stacker, you can load a new tape by issuing: 
# tape390_display -l "NEW TAPE" /dev/ntibm0
NEW TAPE is a message that is displayed on the display unit of the tape device until the tape device receives the next tape movement command.