Recover from a bad flash

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Revision as of 15:35, 20 June 2006 by 220.68.231.238 (Talk)
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So, you're afraid you've bricked your router. Don't worry, there are a number of things you can try to get your router working again before giving up and living with the fact that your router is now a paperweight.

The WRT54G Revival Guide includes step-by-step instructions how to get your Linksys router working again.

The first step is to download the correct firmware for your router from the Linksys Download Page, and follow the Linksys-approved method of reloading the firmware onto the router using the Linksys "Firmware Auto-upgrade Utility". If you can't find "Firmware Auto-upgrade Utility" use "Setup Wizard" as an alternative from other Linksys router (make sure to use your router's firmware). You should also set your network card to 10mpbs and half-duplex, and the Revival Guide gives step-by-step instructions how to do that for different versions of Windows.

The Revival Guide, however, is somewhat dated.

In the section Revival tip #1:Reloading the firmware, if you try to ping 192.168.1.1 and it does not work, make sure that you have a valid static IP address of the form 192.168.1.x. If you do not, the DHCP might not be working on the router even though networking is. So set your IP manually to something like 192.168.1.77 with 192.168.1.1 as your gateway and then try pinging the router again.

Now this is very important, power the router on with a continuous ping running in a command window. You should see at least some seconds, at least 2-3 pings, where it responds to ping of 192.168.1.1 address. Do this several times to be sure. If it does you have good chance of simple recovery. Especially if previous firmware set the boot_wait variable to on, the router pauses even longer than normal during bootup to accept a recovery flash. All you need to do is provide a firmware to it via TFTP during this window of time.

So prepare your PC, firmware file and TFTP software and play with the timing of powering it on and starting the TFTP session just after applying power. If you try it a number of times (at least 10) you will probably rescue the router with no fuss!

If the Linksys-approved method does not work for you, the Revival Guide includes a second technique that involves snapping open the plastic case of the router and using a small metal tool (or paper-clip) to "short" two particular "pins" on the circuit board. It is quite clear that this carries risk of permanently damaging your flash via static discharge, and should be a measure of EXTREME last resort not the first thing to try. You can very likely recover from a bad flash WITHOUT opening the router if you have some patience with the TFTP technique.

There's also a collection of pointers and tips on how to recover from a bad flash at the external link location, but most of the information in that forum seems to have been collected into the WRT54G Revival Guide. So far this is just a starter wiki. If someone could move the important parts into this wiki, that'd be great. Probably organize it by recovery methods and list variations of each method below the method, or something.

External Links

The Wrt54g Revival Guide - Excellent step-by-step instructions (with color photos)

Note that contrary to the instructions, some Linksys cases are secured by screws. Just remove the two front rubber feet to get access to the screws.

How-To: Recover from a bad firmware flash. - Question and Answer Forum 5671278872754261383805 42710235753680640574988

Reviving the Buffalo WHR-G54S

If you have already tried pinging the Buffalo continuously through hard and soft resets, unplugging, plugging and any combination thereof, then you will need to open up the device in order to revive it, similar in practice to the WRT54G Revival Guide Method #3.

  1. Unplug the router, and slide off the side trim panels. One will be covering a torx screw.
  2. Undo the screw and open up the router.
  3. With the router unplugged, plug a patch cable into one of the 4 LAN ports on your router and plug the other end into a computer.
  4. Configure your network card on your computer with a static IP address: IP: 192.168.11.2, NETMASK: 255.255.255.0, no gateway.
  5. Run a the ping command in a terminal or command prompt. In Linux: "ping 192.168.11.1". In Windows "ping -t 192.168.11.1" so that it doesn't stop trying to ping after 4 pings.
  6. Locate pin 12 on the flash memory chip. It is the 12th pin counterclockwise from the dimple in the surface of the chip. See the specs for this chip here.
  7. Short this pin to ground (bare solder around antennas, screw points).
  8. While holding the screwdriver there, plug in the power and watch your ping screen. You should see the pings starting to succeed.
  9. Remove the screwdriver and the pings should continue.
  10. Now use the tftp method to rewrite the firmware.