Find the bandwidth hog by viewing all network connections passing through your DD-WRT router

Something was using all of my upstream bandwidth, wasn’t sure what device or who it was (had friends over). To get to the bottom of it quickly, a simple command can be run from the DD-WRT web-based gui that will show all network connections on your DD-WRT router.

Just follow these 5 easy steps below:

1. Login to your router’s web interface.

2. Click the “Administration” tab, and then click the “Commands” tab.

3. In the text area to enter commands, enter this:

4. Click the “Run Commands” button below where you entered the command above.

Once you’ve clicked the “Run Commands” button, wait a few seconds, and you’ll eventually see some output similar to what you see in the image above, below is the raw text from the image:

Now the key to tracking down the offending user/device is to look for a source IP (almost always a non-routable IP, like 192.168.1.x, 10.10.10.x or whatever) that shows up a LOT more often than other non-routable IP’s.

Once you’ve found that IP, go to the “Status” tab in the DD-WRT web interface, click “LAN”, find the IP that you suspected was the culprit from above and make a note of the MAC address associated with that IP.