NOTE: Replacing the factory firmware is different for every router. In this example we will replace the firmware on a Linksys WRT54GL .If you have a different router, find your solution here to replace the factory default firmware with DD-WRT.
Is it possible to reconfigure one of the LAN ports on a WRT54GL (running Tomato firmware) to act as a second WAN port? I have the following networks: PPOE connection to ADSL modem (works fine on the normal WAN port) WiFi neighbourhood network (in 178.X.X.X range), via a Mikrotik routerboard ; which I'd like to put on the WAN side of the router. Linksys WRT54G2 v1.3 & WRT54GS2 v1.0 - DD-WRT Wiki Use the firmware upgrade dialog to flash Vxworkskiller-G2V13.bin. WAIT for at least five minutes before you continue! (longer is better) Give vxworks killer plenty of time to do its magic! You will not be able to browse the WRT54G2V13 at this point, but you should be able to ping 192.168.1.1. Linksys WRT54GL with Tomato Firmware not connecting to May 14, 2012 Tomato Firmware/Supported Devices - Wikibooks, open books
The WRT54G v1 through v4 all work with Tomato or DD-WRT. v5 is a completely different animal with half the memory, but the WRT54GL is the same as WRT54G v1-4 and will work. This information is available in great detail on the Tomato and DD-WRT web sites. -Mike
DD-WRT and Tomato: Which Is the Best Router Firmware? Jun 20, 2016 WRT54G2 Tomato? - Linksys Community The WRT54G v1 through v4 all work with Tomato or DD-WRT. v5 is a completely different animal with half the memory, but the WRT54GL is the same as WRT54G v1-4 and will work. This information is available in great detail on the Tomato and DD-WRT web sites. -Mike
Tomato for Linksys, making Wi-Fi better | Computerworld
The WRT54GL router must already have dd-wrt installed before you begin this process. 1 -First start by backing up your current CFE.BIN file and keep it in a safe place 2- Enable ssh services in the dd-wrt configuration at 192.168.1.1. Tomato firmware for Linksys WRT54G router Oct 11, 2008