Network Monitoring Options?

Nom du Keyboard asks: "We have a LAN network of 7 servers and about 400 PCs. Every so often I'll notice immense slowdowns, from minutes to occasional delays of a couple hours, while getting data from various servers, and it happens from more than just my PC. So far we haven't had any way of determining if a server has suddenly gotten tied up, or if there is some failure in the communications backbone. Without a lot of money to spend on this (I think it's more important than others right now), what cheap or free monitoring options are there available that can map and isolate problems in a network of this size?"

Comments

tried

[nocomment]

Cacti? ettercap/ethereal/whatever? Ran snort to see what kind of traffic is on your network? You left out an awful lot of information. I'm assuming you are running switches, but who knows? You never said the speed of your network either. Whether this is all in one building or spread across many, with routers in the middle etc... Without knowing any details I will suggest Cacti, and leave it at that.

Free option

[obeythefist]

Start -> Programs -> Administrative Tools -> Performance

If you don't know how this tool works, please resign and hire a high school MCSE who does. But just in case you do want to use /. as a means to make yourself appear more competent at support than you actually are, here's what you do with it. Place counter logs on servers experiencing poor performance. Observe any thresholds that are exceeded that shouldn't (poor disk, cpu, memory, network performance). Upgrade/fix deficient performers. If you don't see any problems, it is likely an issue with network infrastructure (But don't run straight to blaming the network if you haven't fully investigated server performance).

I don't mean to flame but monitoring performance is not complicated and certainly not something that should qualify for an Ask Slashdot.

What will we see next on Ask Slashdot?

"I am an Administrator for a medium sized busines with 100 workstations and 8 servers. We have a new employee starting next week, and I have been told this employee does not wish to use an existing user account, instead management wants the new starter to have an account with her own name on it. I have read through all the manuals but I want to know, is it possible to have a new user account on the network? Management don't want to spend any more money on licenses so this should be a cheap solution."

"I am running a local area network with about 10 desktops and 2 servers. Suddenly last week all the computers stopped communicating. I looked at the core network switch but it appears normal, although all the lights have turned off. Management would like this fixed as soon as possible but they are on a tight budget. Are there any open source solutions, or any readers who have seen similar problems?"