Hi!Toomas,

I've indicated 40Gb because my PowerVault is configured as yours, to compress 
data by hardware ( I think in a 2:1 ratio by default). I don't use any software 
to compress data, and all the data I should backup are locally to server. Do 
you think  in this scenario will I have problems with amanda if I indicate 40Gb 
-tapes in my descriptors (or seemed, 35Gb if 40Gb is too much optimistic) ?  

I will make use of your filemark and speed values, much thanks ;-)

Best regards,

----- Original Message ----- 
From: "Toomas Aas" <toomas.aas AT raad.tartu DOT ee>
To: "Ra.l Wild-Spain" <rcruz AT wild-spain DOT com>; <amanda-users AT amanda 
DOT org>
Sent: Tuesday, February 25, 2003 5:56 PM
Subject: Re: Q: simple but how ?


> Hi!
> 
> > define tapetype DDS-4-40{
> >  comment "DDS-4 PowerVault with compression"
> > DDS-4-20
> >  length 40000 mbytes
> > }
> 
> This length number is probably too optimistic. This assumes that your 
> data compresses with a 2:1 ratio, which is rarely seen in real life. 
> FWIW, here's my tapetype with DDS4 drive using hardware compression:
> 
> define tapetype DDS4 {
>    comment "DDS4 using hardware compression"
>    length 25000 Mbytes
>    filemark 0 Kbytes
>    speed 2816 Kbytes
> }
> 
> The length number is really just a guess (I think I underestimate the 
> compression a little, but since I only have 10 GB of data this is not 
> an issue for me right now). The speed number is taken from "avg tp 
> write rate" as reported by Amanda's nightly run.
> --
> Toomas Aas | toomas.aas AT raad.tartu DOT ee | 
> http://www.raad.tartu.ee/~toomas/
> * One way to be happy ever after is not to be after too much.
>