On Wed, May 21, 2003 at 12:11:13AM -0400, Jon LaBadie wrote:
> On Tue, May 20, 2003 at 07:47:08PM -0700, Stephen D. Lane wrote:

> And DIP switch 8 off too?  And software selected no compression with
> either mt command or with appropriate device selection?

DIP 8 was/is OFF - my writing error (see below).  I gave it a 
'mt defcompression -1', but I've no clue if this actually 
accomplished anything...

> In 2.4.4, when you upgrade, there is a new version, amtapetype.

Sounds good :)

> > My comments/questions:
> > 
> > 1) tapetype's output is obviously more conservative than what I've been
> >    using, both in terms of the total tape length and in terms of the
> >    filemark size.  I'm not sure if this is a good thing or not, the
> >    obvious pros (amanda is less likely to overrun the end of the tape)
> >    and cons (she won't put as much data on the tape if the tapetype
> >    estimate is short) aside.  Any thoughts on this?  Can I trust
> >    tapetype?  How far?  (I'm hoping to get a quick answer from someone
> 
> No, you can't trust tapetype.  It is put there just as a joke.  Gotcha.
> In reality, all tapes hold about 40 percent more than the manufacturers
> claim.  They hope you will buy more tapes when you think they hold less.

Well, cool, then!

> >    Also, a 2.7MB filemark seems really large (so does a
> >    1.5MB filemark, for that matter... The DEC-DLT2000 tapetype in the
> >    tapetypes file has a 15000 mbyte length and the file mark is only
> >    8KB...).  Why might/must these be so large?
> 
> 5/1000ths of 1 percent?  You are concerned about 0.005%.  If you wrote
> 200 dumps to the tape, it would still only take 1% of the tape for those 
> marks.
> Its effect on Amanda calculations, no matter how large, is quite small.

Not concerned, just curious - a purely academic viewpoint :)  It still
seems large...

> Check your manual again, my reading says DIP 8 on DISABLES software control.

Oddly enough, that's also what my manual says :)  DIP 8 is OFF to ENABLE
software control, and that's how the drive was, and is, set.

Thanks,

--Steve Lane               /"\
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