ntbackup compression

[Neil Jarman]

Hi,

Does NTBackUp support hardware compression on an HP DAT 20/40 (DDS4)?

I have the compression switch on, but I don't seem to get much over 20Gb
before the tape is full.

Many thanks,

NEIL

 

[Andrew Morton]

Hi,

Does NTBackUp support hardware compression on an HP DAT 20/40 (DDS4)?

I have the compression switch on, but I don't seem to get much over
20Gb before the tape is full.

Many thanks,

NEIL

It depends on the compressibility of the data you're saving to tape. For
example, .exes, .jpgs and .zips will not compress very much at all
whereas plain text may compress very well.

Andrew

 

[abram]

Open Device Manager, right-click the tape drive, select Tape Drive
Parameters, check whether 'Compression Capable' is TRUE.

 

[Enkidu]

Does NTBackUp support hardware compression on an HP DAT 20/40 (DDS4)?

I have the compression switch on, but I don't seem to get much over 20Gb
before the tape is full.

I'd say that on DAT you should be able to approach 1.7 compression.
That is the *best* that you can hope for with normal type data, so you
tape could hold *up to* 34GB best case. If you have a lot of
compressed data then you could be down to 1.2 x or 24GB on even less.
These are "rules of thumb", what I have seen in practise.

Cheers,

Cliff