If you are running a server its always a nice, and usually a good, idea to find out whats using your bandwidth to identify slowness or to find out who on your network
is consuming the most.
IFTOP
Iftop is a Linux command-line program designed to give you live statistics about what network connections use the most bandwidth in a nice graphical form. As you may realise from the name, iftop borrows a lot of ideas from the always useful load troubleshooting tool ‘top’. Like top, iftop updates automatically every few seconds, and like top, by default, it sorts the output you see by what’s using the most resources. Where top is concerned with processes and how much CPU and RAM they use, iftop is concerned with network connections and how much upload and download bandwidth they use. Iftop is packaged for both Red Hat and Debian-based distributions – it’s probably not installed by default, so you will need to install the package of the same name. Once it’s installed, the simplest way to get started is just to run iftop as the root user. Iftop will locate the first interface it can use and start listening in on the traffic and display output in a similar fashion to the basic top command: http://www.ex-parrot.com/pdw/iftop/
NTOP
Ntop is a network traffic tool that shows network usage in a real time. One of the good things about this tool is that you can use a web browser to manage and navigate through ntop traffic information to better understand network status.
Also Ntop monitors and reports hosts traffic and supports these protocols:
- TCP/UDP/ICMP
- (R)ARP
- IPX
- DLC
- Decnet
- AppleTalk
- Netbios
- TCP/UDP
Ntop can be managed through a web interface. You can enter your server address in your web browser:
http://ServerIP:3000
https://ServerIP:3001
http://www.ntop.org/products/ntop/
The above are 2 very simple tools to install. If your setup is more complex it maybe worth installing something similar to cacti, but for on the fly checking the above 2 tools can be installed in minutes and help diagnose issues.
