On Sun, 25 Apr 2004 at 11:07am, Thomas M. Andersen wrote

> I'm about to setup a Amanda-server in my network. I need to go buy some
> hardware but i'm not quite sure what it's going to be.
> 
> I looking at a 2U Xeon SCSI rack machine with Sony AIT-2 tapestreamer and
> 150 GB harddrive. Does it have the power/size to handle my backup?
>
> I have a total of 12 machines (mostly linux) with a total of about 3-400
> GB that needs to be backed up.
>
> The objective is that the backup has to be done within 6 hours without
> changing tapes more than once a day.

Is that 3-400GB every night, or over a dumpcycle?  If the former, you'll 
need a faster tape drive.  Sony claims 15MB/s for AIT2, but that's 
assuming 2.6:1 compression.  So native tape speed is about 5.8MB/s, which 
gets you ~20.7GB/hr, so about 120GB in your 6 hour window.  If the latter 
and your dumpcycle is long enough (even a week would be long enough), then 
your tape drive is up to the task.

As for the server itself, you're probably woefully overpowered.  I 
currently back up ~200GB/night to 2 AIT3 drives hooked to a single PIII500 
with 384MB of RAM and 2 *large* IDE disks for holding space.  Amanda needs 
very little in the way of CPU, unless your clients are slow and thus you 
want to do server side software compression.  In either case, SCSI is 
probably overkill *and* will limit how much holding space you get.  
Holding space is good.

Basically, if you have any older servers lying about that you can stuff a 
large IDE drive or two in, those will work just fine as amanda servers.  
If you can buy new, a single P4 or Athlon is more than up to the task, and 
IDE drives will save you money and get you more holding space.

Good luck.

-- 
Joshua Baker-LePain
Department of Biomedical Engineering
Duke University