How can I monitor network performance in Linux?

Question

I am managing a network with a Linux server (CentOS 5.4) and Windows XP Clients. Recently I have become concerned about network performance and would like to begin monitoring it. Is it possible to monitor network traffic in order to find ways to optimize traffic? For example, there are some users who stream internet radio to their machines. I would like to find out if it's eating up enough bandwidth to require that they stop. Another possibility would be for me to see if performance is slowed by large file transfers between a cleint and the server. It would also be helpful to have some sort of reporting that would allow me to see peak load times in order to better schedule network maintenance tasks. Are there any utilities available that would help me accomplish this?

Thanks,

Mike

Solution 1

Look for iptraf and iftop, two tools that will help you a lot. You can run then in the gateway machine (if you have one) or specific hosts.

If you want to graph something you can use a SNMP tool like Cacti, Zabbix or even MRTG to have statistics of how much each host is eating from your bandwidth.

Solution 2

ntop sounds like a program for you.

Comments

[gravyface]

Can you expand your question to include some details about your network equipment? i.e. do you have any managed switches? Is the CentOS server also your gateway router? If not, what are you using as your gateway router?

[mclark1129]

gravyface, I am not using any managed switches, and my gateway router is a Fortigate 60. Clients do not pass through the server to get to the internet.

[symcbean]

-1: iptraf and iotop are useful while you can afford the time to site and watch them - not for long term stats gathering. You can only use an SNMP tool if the traffic is passing through an SNMP capable router.

[coredump]

It's iftop. And SNMP is just a matter of adding a SNMP server to the hosts, there's no need to be only "routers". Also, you can log data with iptraf and analyze it later.