On Tue, Aug 13, 2002 at 09:05:02AM +0100, Kevin Passey wrote:
> Hi,
> 
> I have just run tapetype for the above drive - it looks like this.
> 
> ./tapetype -f /dev/nst0
> wrote 530067 32kb blocks in 1621 files in 7441 seconds (short write)
> wrote 530076 32kb blocks in 3252 files in 7408 seconds (short write)
> 
> define tapetype unknown-tapetype {
>     comment "just produced by tapetype program"
>     length 16564 mbytes
>     filemark 0 kbytes
>     speed 2284 kps
> }
> 
> I have used a 150m DG4-150 Fujifilm 4mm tape.
> 
> I presume I just include this code in the amanda.conf file.
> 
> One question I need help on - does it matter that the tapetype is un-known -
> or can I just include it like this:-

There can be multiple "tapetype definitions" in amanda.conf.  There is also
one that is used, specified with the "tapetype ..." directive.

If you want to specify "tapetype unknown-tapetype" then you can include
the above definition as is.  :))

My recollection of dds4 format is approximately 20GB uncompressed capacity.
More like 19.6 when actually measured by tapetype.  However if you run
tapetype with hardware compression turned on, then the "apparent" capacity
of the tape decreases to about 70-90 percent of uncompressed capacity.

Your 16.5GB measurement suggests to me that HW compression was on during
the tapetype run.

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