[NTLUG:Discuss] Monitoring a Network

[Preston Hagar]

On Wed, Jun 9, 2010 at 6:26 PM, Dennis Myhand <dmyhand at suddenlink.net> wrote:
> I am about to start a new position at the school district I work at.  My
> position will be Technology Coordinator and the district is small enough
> that the position will include computer repair, deployment, and maintenance
> as well as maintaining and improving the network, and planning for future
> expansion.  My question is, what network tools are available to me to keep
> an eye on things and see what is happening on my network?  One problem we
> have had this last year, and what played a big part in the most recent
> technology coordinator deciding to leave, was a big slow down in network
> speed.  He said it was too many people surfing the net and downloading video
> that caused the problems with network speed.  I have no doubt that was a
> part of the problem.  But there were also network devices he installed which
> brought the network to a halt and then had to be uninstalled.  I am not sure
> that the network was reconfigured properly because speeds never seemed to
> return to normal. We have 6 DS-1 lines which will be connected this July.  I
> am wanting to know what I can use to see what is happening on the network.
>  The guy I am replacing was a M$ only guy.  I am willing to use whatever
> tool is available.  I prefer Debian but will use SuSE or CentOS.  Please,
> let me hear your advise.  Thank you, Dennis Myhand
>
> _______________________________________________
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>

You might want to look at MRTG:

http://oss.oetiker.ch/mrtg/

Depending on how small your network truly is.  It doesn't have a ton
of features like other "enterprise" level systems, but does create
nice, easy to read graphs for each port on your switches.  I have used
this at several small businesses to easily find the bandwidth hog(s)
of the office.  I can just look at the graphs/pages and see which
ports have high traffic.  I then go to those jacks and find out what
is plugged in and what it is doing.

MRTG is purely informational, it won't let you configure any kind of
routing, QoS or anything like that and it doesn't even separate things
out into different protocols/ports etc, it just reports raw traffic.
It does this really well though, is free, and is fairly easy to setup.

Preston