[NTLUG:Discuss] Monitoring a Network

[CoryC]

> Message: 2
> Date: Wed, 09 Jun 2010 18:26:35 -0500
> From: Dennis Myhand <dmyhand at suddenlink.net>
> To: NTLUG Discussion List <discuss at ntlug.org>
> Subject: [NTLUG:Discuss] Monitoring a Network
> Message-ID: <4C10232B.6070106 at suddenlink.net>
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> 
> 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
> 
> 
> 

In my non-profit environment I use the following free setups for a 100 user/workstation network:

Zenoss for traffic monitoring of SNMP enabled firewall/switches/servers.
EasyIDS for intrusion detection on inside of perimeter firewall. Includes NTOP with lots of graphs. 
Squid/Dansguardian for internet content filtering (stops streaming audio/video). 

Depending on your situation you might be able to use Endian Firewall as your firewall since it has the content filter built into it and some intrusion detection capabilities.