On Thursday 15 August 2002 12:19, Kevin Passey wrote:
>What is the best size for a holding disk - is it a "how long is a
> piece string" or are there some optimal values.
>
>I have 2 servers I want to back up - the Amanda server 40gb RH
> Linux box - an WIN NT machine 16gb.

Holding disk sizes are rather hard to pin down, and most of us seem 
to solve that problem by specifying a /path/to which puts it on a 
large partition, and then specify a reserve of a couple of gigs.

amanda can backup to it while simultainously dumping from it, 
essentially useing it as a giant circular buffer with certain size 
limits stated pretty much up front.

Those are:

1. No disklist entry should ever exceed the size of a single tape 
since amanda can't span to the next tape with a single operation.

2. If there are filesize limitations such as 2gigs on the server, 
then the chunksize will need to be sized less than that, otherwise 
its a never mind.

3.  The reserved amount should be able to hold at least the 
incrementals of the whole system, a rather unpredictable value at 
best...

I started out with about 27 gigs when I first set this machine up, 
but have eaten up several of those with source code, pictures from 
my new digital camera, and music from 'ogg'ing my cd collection, so 
I'm down to about 12 gigs which is still overkill on a 2 machine 
system with about 90 gigs worth of disk, not all of which is full 
of course.  I *might* have 40 gigs worth of Junque or data, 
depending on how one defines the words.  Amanda uses a 7 day 
dumpcycle here, with 20 tapes, and it normally fits a given nights 
activity onto one 4g tape.

-- 
Cheers, Gene
AMD K6-III@500mhz 320M
Athlon1600XP@1400mhz  512M
99.11% setiathome rank, not too shabby for a WV hillbilly