Tuesday, October 18, 2011

Linksys WRT54G firmware fun.

At work I use the famous blue and black WRT 54G. It (is not mine nor my choice) has done fine, but lately started dropping the WiFi.

I got admin access and looked at the firmware...it was original to the Ver2 (linksys now has V8) . So I went to the Linksys site...which is now a Cisco site...went to support/firmware/Ver2. They list 4.21.4 as the current firmware, so I downloaded it, and updated the WRT54G with it.

Obviously, since I am posting here, the update didn't go well. It ended with the power light continuously flashing. No combination of holding reset button, cycling power etc. would fix it.

So off to the internets...luckily my Android phone has 4G and the PdaNet sofware, so I had my laptop up on the internets within a minute or so.

I had to browse a ton of websites, but this one was best.

I had my laptop with the ethernet port set to 192.168.1.2 and the speed 10half. I then started a ping on 192.168.1.1 with the command window "ping -t 192.168.1.1" and left it pinging away.(with no response)

Like I said, I had done the reset button and power cycling a few times...so now it was time to crack open the case and tempt fate.

I pulled the power from the linksys, put a ballpoint pen between pins 15 and 16 (as shown in link) and put power plug back in (while watching the ping running)...after a few seconds I started getting a response.

I left the ping running and ran the TFTP.EXE software, with 192.168.1.1 as the address, admin as the password, and that downloaded 4.21.4 firmware again...90% through the update it crashed again.

So obviously that firmware is defective...so now what, you can't find older firmware on the Cisco site...back to the internets...eventually I found some posts complaining about the 4.21.4 firmware, and recommending the 4.21.1 firmware...with a link to a cisco page (sorry you will have to find it yourself...I already closed those web pages)

I went back through the ballpoint pen shorting pins 15-16 ping test again...ran TFTP again, but this time chose the 4.21.1 firmware...it went all the way through and said success, and the lights on the router were normal...from then it was as it should be.

So moral of story is...don't use firmware 4.21.4 on your Ver2 WRT54G...