Technology Insights

Use Wireshark And DD-WRT Router Firmware To Imitate Port Monitoring On A Router Switch Port

Earlier today I needed to find the quickest and easiest way to monitor all traffic to and from a specific device on my network. The goal was to see how much bandwidth based on a specific amount of time that the device was using. My initial hope was that I could configure port monitoring on my WRT54G running DD-WRT firmware however I quickly found out this is not an option. I eventually settled on adding a couple iptables commands that would send all traffic destined for or sourced from a specific IP address to another IP address. Follow the directions below to add the iptables commands to a router running DD-WRT firmware and then to capture the traffic on a computer running Wireshark.