0 comments
2nd Apr 07
Mohammed Alani
When would you need this: When you loose the secret, enable, or console password of a 2500 Cisco Router.
Special Requirements: None.
1. Interrupt the router booting operation. This is done by pressing (Ctrl+Break) keys 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 11.0(10c), SOFTWARE
Copyright (c) 1986-1996 by cisco Systems
2500 processor with 14336 Kbytes of main memory
Abort at 0x1098FEC (PC)
>
The (>) 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:
> o/r 0x2142
This command will change the sixth bit (originally the configuration register is 0x2102) to one. By doing so, the router will act as new in the next boot, i.e., the router will not look for the startup-config in the NVRAM.
[sniplet adsense]
Read the rest of the article in the Router Geek Book: Guide to Cisco Routers Configuration
