LinksysWrt54GlUpgradeToDdWrt

Making your Linksys WRT54GL wireless router open source with dd-wrt

Home wireless routers are actually pretty complex computing devices and many of them run some sort of stripped-down linux or some other embedded OS such as VxWorks. When I purchased my Linksys wireless router 5 years ago I specifically bought one that could be upgraded to run an alternative open linux platform such as dd-wrt.

Well for five years I never bothered to upgrade the firmware because the wireless router worked fine as-is. However, I finally decided to upgrade for a few of reasons:

• I wanted to know who was using my wireless network.
• My macbook had started randomly dropping wireless connections.
• I wanted to be able to ssh in to my wireless router.
• I didn't want to lose any more geek cred.

I then investigated which alternative router firmware packages were available. When I purchased my router Linksys had just created a new model: the WRT54GL. This was similar to the existing WRT54G in that it had 4MB of flash ram. After the WRT54GL was released Linksys reduced the amount of flash on the straight 'G' model to just 2GB to save manufacturing costs. While it is possible to replace the flash on just about all WRT54GX models the GL is simplest. So if you have a regular G or a GS model, read on because some of these tips will apply for you. Just remember that you may not be able to install all the coolest features on other models. Also apparently you can't replace the firmware on the version 7 WRT54G model at all. Most other models can be upgraded.

The first step was to pick an appropriate replacement OS for the router. This extremetech article does a nice job of covering the possible alternatives. I went with dd-wrt because according to the article it was completely open-source and free, and easy to install. This guy agrees with me on that.

The dd-wrt website is unfortunately confusing, mostly due to the vast number of different wireless router makes and models it supports. This specific wiki section pointed me in the right direction. Be sure to read the top of that page which details how to definitively identify which router you actually have, as Linksys makes this quite confusing.

From everything on that page, I knew the correct sequence was to first install a 'mini' version of the dd-wrt image, and from there install a 'std' (standard) version. This is because some versions of the existing linksys firware have a 3GB flash image limitation, and the std version is alrger than that. While the notes indicate that you may be able to install the std version directly depending on what linksys firmware you have installed, it is safest to do the mini version first, then the standard version.

I downloaded both the v.2.4 sp1 consumer mini 1.1 firmware and the corresponding std firmware onto my Mac. Then I plugged my mac directly into my wireless router with an ethernet cable in case anything went wrong.

At this point I had the router back up and running as before, but with a ton of new features. One thing I love about dd-wrt is that you don't have to use any of those features if you don't want to so you can leave it alone or experiment further.