DD-WRT revisited

Posted by Tejus Parikh on September 4, 2006

A few weeks ago I blogged about the difficulties I faced in upgrading the two Linksys WRT54G’s on my network to the DD-WRT firmware. The goals were pretty simple. The DD-WRT is just a much better interface for that box. However, for some crazy reason that I simply couldn’t figure out, one DD-WRT worked fine, but two didn’t. My solution at the time was to reflash the original firmware on one of the routers. However, one of the lines for the instructions for vx works killer stayed in my memory and resurfaced rather randomly a few weeks later. To quote point 2:

Download [vxworks_killer_g_v06.zip] and extract, OR create a custom firmware image with your MAC address embedded in it. See the ‘Changing your MAC address’ section below for more information.
Hrm… Why would I need to create a custom image with new MAC’s? Well maybe because the originals got replaced as part of the upgrade. I’m sure that having identical MAC’s on a network would cause all sorts of crazy problems just like I was experiencing. I pulled the AP back out of the ceiling, booted up Windows and reflashed the box with the DD-WRT image. Lo and behold, the MAC address for all ports were identical. From then on, it was a simple matter of telneting to the device (old school!) and running some commands. To figure out what addresses I needed to edit, I had to enter: nvram show to find out what values I needed to change. Once I figured that out, I could set the parameters by using something like the following: nvram set et0macaddr=00:90:4d:83:00:01 To commit the changes, I had to enter: nvram commit After a reboot, the system came up with a new mac address and co-existed happily with the other AP on the network. The final step was the bump the Tx power and attach the new antennas for a nicely boosted wireless range.

Tejus Parikh

Tejus is an software developer, now working at large companies. Find out when I write new posts on twitter, via RSS or subscribe to the newsletter: