/dev/nst0

[Paul Howarth]

Beast wrote:
> stephan.helas at e-7.com 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.