On Thu, Apr 29, 2004 at 07:59:51AM -0700, Dege, Robert C. wrote:
> 
> Every so often, I'll run the following command to quickly see which amanda 
> tape is currently in my tape drive:
> 
> # dd if=/dev/nst0 bs=32k
> 
> Most of the time, I'll get the header information, but every so often I have 
> to run the command twice for the system to successfully read the tape.  i.e.:
> 
> bash$ dd if=/dev/tape bs=32k
> 0+0 records in
> 0+0 records out
> 
> bash$ dd if=/dev/tape bs=32k
> AMANDA: TAPESTART DATE 20180319 TAPE SIMNET-02
> 
> 1+0 records in
> 1+0 records out
> 
> 
> Any idea why this happens?

I tend to use mt and mtx manually a good bit.
Often when I do an "mt status" it shows some error condition.
Then a second mt status works normally the actual status.

Doesn't explain why the "error condition" exists, but if you are
seeing the same thing, maybe the first dd is seing the error,
that clears it, then the second one works.

-- 
Jon H. LaBadie                  jon AT jgcomp DOT com
 JG Computing
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