Bandwidth is not free, and if you were to believe everything ISPs said, you might believe a war over bandwidth will be as violent as one fought over oil. With ISPs throttling bandwidth, and hosting companies fighting for every last cent of bandwidth, it is no surprise that the word bandwidth can strike fear in the heart of a system administrator. The truth is that bandwidth is costly, but the scarcity of it is not nearly as great as ISPs claim. Nevertheless, they will make you pay for it, so you should do everything you can to monitor it, track the services using it, and find out exactly how it is being used.
One free and open source tool that can help you monitor your dedicated server’s bandwidth is called BandwidthD. It produces web-based output on static HTML pages or dynamic PHP pages, depending on your preference. BandwidthD offers the following features:
- TCP/IP tracking
- Graphs and charts for bandwidth usage
- Individual IP usage
- Displays utilization over 2, 8, 40, and 400 day periods
- Logging intervals of 3.3 minutes, 10 minutes, 1 hour, or 12 hours
- Tracks HTTP, TCP, UDP, ICMP, VPN, and P2P all in color coded graph entries
BandwidthD is a cross-platform application, running on Linux, all BSD platforms, Mac OS X, Solaris, Unix variants, and Windows. It is free and open source software released under the GNU GPL. You can freely download the software from the project’s website. You can also view a demo of the software running, as well as screenshots, on the website.