Fred,

Fact
The options are not exclusive. You can SW compress on the client
or on the server or in the HW having nothing to do with the choice
of dump v tar.

Opinion
HW compression is great if you are trying to save CPU on the client
or server, but doesn't allow you to estimate tape usage as well since
amanda doesn't learn from the drive what the compression ratios are
for the file systems you are dumping.

er, I should say the DLE - disk list entries, since tar allows you
to put to tape (or disk file) things other than "partitions".

                                        YMMV

On Mon, Aug 23, 2004 at 02:52:29PM -0400, Frederic Medery wrote:
> Hello, I'm using amanda with IBM 3581 tapechanger,
> my tapetypes.conf is :
> 
> # IBM LTO Ultrium 3581 tape Charger
> define tapetype IBM-LTO3581 {
>         comment "IBM LTO Ultrium 3581 (Hardware Compression off)"
>         length 100608 mbytes
>         filemark 0 kbytes
>         speed 13120 kps
> }
> 
> 
> I'm gonna use dump instead of tar so I want to enable hardware 
> compression, but I can'y find any in the amanda doc ?
> 
> Some Hints ??
> 
> Thanks !!!!
> 
> -- 
> Frederic Medery
> System Administrator
> 
> LexUM, University of Montreal
> 
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