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Cisco: Resetting Forgotten Password

I was actually made to write this blog after I end up buying a password protected Cisco 2500 router from Ebay. My room mate collected it and straight away tried to connect it to HyperTerminal as he wanted to test his newly learnt skills from CCNA classes. But more to his disappointment, the router was password protected and it was not until evening when I returned home after work.

If you do end up in a similar situation, before you start have your snacks, roll up your sleeves and be prepared for a good 3-4 hrs of command line drill.

Alright.. my bad.. it won’t take this long, it’s actually easier than it looks and can only take a max of 2 minutes if you got all the right stuffs with you.

And here is how we do it in easy steps:

1) Connect to your router via console.

2) Power reset the Router.

3) When the router boots again, Press "Ctrl + Break” or “Ctrl +Pause”(Hyper-terminal/Putty). Pause/Break is actually the same key. And make sure to do this with in within 60 sec. And if you are using:

Telix: Ctrl+End

Procomm: Alt+B

And if the cable is good and the BREAK signal is correct, the router should boot to a router> prompt. Well done…

4) Type o/r 0x42 at the “router>” prompt.

Well the command doesn’t make much sense if you are a newbie and for time being I won’t go into much details and anyway who cares if these magic command do the job..

Well as an overview all I can tell is, this tells the router to boot from the Flash Memory without loading the configuration file.

5) Type “i” and press return.

Woollaa.. The router will reboot and after reboot it will take you to the configuration wizard. You may continue with it or press Ctrl+C to break.

Type enable at the router> prompt. This will put you in enable or Privileged mode and the prompt will look like this: router#

Thats it.. your router is now password free.. n good to go…

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