Jon LaBadie wrote:

On Mon, Feb 07, 2005 at 10:07:50AM +0200, Shai Ayal wrote:

define tapetype DLTVS160 {
  comment "DLT VS160 tape drive"
  length 74529 mbytes         # 72.78 Gb
  filemark 584 kbytes
  speed 2203 kbytes           # 2.15 Mb/s
}

So my tape is configures with it's uncompressed length. The backups seem to be working as expected, but how to make sure there is no hardware compression ?

I suspect that when you get things sorted out that the amtapetype command
suggested by Paul B in another response will report a higher capacity.
I'm guessing the above tapetype definition may have been made by a "tapetype"
command run with hardware compression turned on.

I ran amtapetype and indeed I have now:

define tapetype QUANTUM-DLTVS160 {
   comment "just produced by tapetype prog (hardware compression off)"
   length 80064 mbytes
   filemark 0 kbytes
   speed 7490 kps
}

Which adds 5Gb to tapelength and more than a 3-fold increase to the speed. I am 
trying to submit this to the hardware FAQ.

Shai


--
Shai Ayal, Ph.D.
Head of Research
BioControl Medical BCM
3 Geron St.
Yehud 56100
ISRAEL
Tel:  + 972 3 6322 126
Fax:  + 972 3 6322 125
email: shaia AT biocontrol.co DOT il