Before backing up data on a device, you must understand the tape device-naming schema:

First tape device name: /dev/rmt/0
Second tape device name: /dev/rmt/1

rmt = raw magnetic tape device

You can also add special character letter to specify density using following format
/dev/rmt/ZX

Where

• Z is tape drive number such as 0,1..n
• X can be any one of following (as supported by your device, read the manual of your tape device & controller to see if all of them supported or not):
• l – Low density
• m – Medium density
• h – High density
• u – Ultra density
• c – Compressed density
• n – No rewinding

For example to specify the first, drive with high-density with no rewinding use device /dev/rmt/0hn.
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