Re: [Sheflug] Linux Network Analysis Tools

["Chris J" <cej [at] xxxxxxxxxxxxxxxx>]

And Lo! The Great Prophet " Chris Johnson" uttered these words of wisdom:
>
> I did find Ethereal http://www.ethereal.com/ with a quick google but
> I'm not sure if it does what I'd like it to.  AFAICT it allows
> inspection of packets on a network segment.

Yep - etherail is a packet sniffer. Great if you're trying to trace
network or protocol problems.

> I'd like to be able to monitor network utilisation
> over a period of time to see how near capacity parts of a schools networks
> are getting and then if they are getting near capacity to be able to
> identify the types of traffic or source and destination so we can see if
> we
> can move the resources closer together or duplicate resources in slack
> periods so they can be accessed locally in busy periods.

MRTG can give an overall view of traffic on an interface (I'm sure you've
seen the graphs) - even the LINX seem to make some use of it :) There's
also a whole plethora of other input modules so MRTG can get it's data not
just from SNMP sources (f'rinstance -- I've seen it do http hit stats,
qmail queue stats, uptime stats, CPU load, memory etc).

As far as identifying types of traffic - again, MRTG might be your best
bet, but you'll need to configure, find, or create your own capture
routine so MRTG can graph it. Doing something with tcpdump or even
ipfwadm/ipchains/iptables byte counters providing the data might work but
I'd have to play first.

I'm sure there are other possible solutions as well, but those are what
immediately spring to mind.

Chris...

-- 
\ Chris Johnson                 \
 \ cej [at] nightwolf.org.uk          \
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