stephan.helas@xxxxxxx wrote:
/dev/nst0 -> non rewinding tape device /dev/st0 -> rewinding tape device
non rewinding means, that device does not automatic rewind after writing to tape.
It depends on tape driver, kernel or hardware? from where i should know that my tape drive is support rewinding or not?
All tape hardware supports rewinding; it wouldn't be much use without it.
You choose for yourself whether to use a rewinding of non-rewinding device entry based on your application. Both devices are for the same hardware but they behave differently. If, for instance, you're just using tar to dump some files to a tape then you'd use the rewinding device so that the tape was rewound after having written the tape so that the tape would be ready to be read whenever you needed it. On the other hand, most higher-end backup applications write multiple files to the same tape, so you would use the non-rewinding tape device node (e.g. /dev/nst0) for that; if you used a rewinding device node then the tape would be rewound after writing each file to the tape and the next file would overwrite the one just written.
Paul.
