Πέμπτη, 29 Δεκεμβρίου 2011

How to Recover Cisco 2600 Router’s Password

How to Recover Cisco 2600 Router’s Password


1. Interrupt the router booting operation. This is done by pressing (Ctrl+Break) key simultaneously as soon as you turn on the router. This step will get you to the ROM monitor mode (rommon).

You will have the following:

System Bootstrap, Version 11.3(2)XA4, RELEASE SOFTWARE (fc1)

Copyright (c) 1999 by cisco Systems, Inc.

TAC:Home:SW:IOS:Specials for info

PC = 0xfff0a530, Vector = 0×500, SP = 0x680127b0

C2600 platform with 32768 Kbytes of main memory

PC = 0xfff0a530, Vector = 0×500, SP = 0×80004374 monitor:

command “boot” aborted due to user interrupt

rommon 1 >

The (rommon 1 >) prompt is for the ROM monitor mode. If you are having a problem interrupting the boot sequence of the router, you might be interested in this procedure to simulate break key sequence .


2. Now you should change the value of the configuration register in order to make the router neglect the contents of the NVRAM in the next boot up. This is achieved using the following command:

rommon 1 > confreg 0×2142

This command will change the sixth bit (originally the configuration register is 0×2102) to one. By doing so, the router will act as new in the next boot.

3. Perform a restart to the router using the following command:
rommon 1 > reset


4. The router now will restart and ask you if you want to use the setup mode and of course you will say no. Now, in order not to loose the configuration that you already have in the router, you should go to the USER privileged mode and perform:

Router#copy start run

This will get you back your old configuration but with one exception, you already are in the privileged mode without having to know the password..!!!!

Now you put a new password or passwords if you may:

Router(config)#enable secret blahblah

And you can also put new console and telnet passwords if you like.


5. To get things going back to normal, change the value of the configuration register to its original form (0×2102) using the following global configuration command:

Router(config)#config-register 0×2102


6. Now you should save the configuration including the new passwords that you know:

Router#copy run start


7. Now reload and you are good to go:

Router#reload

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