484. Putting Tomato (USB) on Cisco/Linksys E2500-AU 300M

Update 18/8/2014: I've since done this on a unit with a BCM5357 chip rev 2 pkg 8 as well:

Update: the more I use it, the more I like it. I really like my old WRT54G, but I'm even happier about my fancy new E2500 since it's faster and all. Flashing them are equally easy. If you prefer some else to do it for you -- or if you want to seek independent confirmation that the router can be flashed -- look at http://flashrouters.com/ . The focus on that site seems to be dd-wrt (which is an alternative to Tomato), but they do list tomato routers too, e.g. http://www.flashrouters.com/routers/cisco-linksys-e2500-tomatousb-router

Original post:
Flashing a router is always a bit unsettling, so here's a detailed how-to.

Anyway, I managed to pick up a Linksys E2500-AU for $45 (Broadcom BCM5357 chip rev 1 pkg 8), which isn't too shabby. Some cursory searching showed that people had managed to put dd-wrt and tomato on it. While my experience with dd-wrt hasn't been that good, I've been running tomato on a linksys wrt45g for a around four years now, without any issues.

There's a number of derivatives of Tomato e.g. Tomato USB, and I'm a bit confused over what sets some of them apart. However, it seems like this Polish site is the right one for me. See here for the 'about' page.

What I'm presuming:
That you are running linux, and that you can afford to brick your router. There is always a risk associated with flashing firmware, and don't make any assumptions about the validity of the warranty...

How to:
Download the firmware:

cd ~/Downloads
wget http://tomato.groov.pl/download/K26RT-N/build5x-110-EN/Linksys%20E-series/tomato-E2500-NVRAM60K-1.28.RT-N5x-MIPSR2-110-Max.bin

With the router turned off, connect it via CAT5 cable to your computer. It should be attached to one of the LAN ports (in my case Ethernet 4) on the router. Ignore what the manual says about plugging into the WAN ('Internet') port.

Plug in power cable to the router.

On my computer I've disabled network manager (sudo rcconf, then uncheck network manager and either stop it or reboot) and my /etc/network/interfaces has this in it:

auto eth1
iface eth1 inet dhcp
ethernet-wol g

You probably won't have to worry about this. Just make sure that you don't have anything interfering with the 192.168.1.0/24 subnet.

Anyway, once you have been assigned an IP address, navigate to 192.168.1.1, and work your way through the annoying warnings:

leave the user name blank, and use admin as the password

 Here's where it get's interesting. Select the .bin file you downloaded and hit ok.

Use admin for both username and password

 I was then met with this, which at first scared me a little:

I unplugged the power from the router, and plugged it in again, and I could log in:

The first step is to erase the nvram, or you might end up with "Cannot proceed: two or more lan bridges have conflicting ip addresses or overlapping subnets" when configuring your network. To erase NVRAM go to Administration/Configuration/Restore Default Configuration - Erase all data in NVRAM memory(thorough).

 You are now ready to start setting up your router.

Go to Administration/Admin access.

Set up an admin password, turn off telnet and change the colour scheme to Tomato. Optional but recommended: disable ssh access via password -- it's better if you add your public keys here.

Go to Basic/Network, and set an SSID and a password for your wireless. Set up your network details -- in my case I have static IP. I also want the subnet to be 192.168.2.0/24 and I use MAC spoofing, which you can set up under Advanced/MAC address.

 And this is what it looks like if you connect to the router via ssh:

So far so good!