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New Member

need help configuring 2500 series

My cisco experience is limited, but here is the deal.

I have a 2501 which has been used for a T1 to an ISP. We changed locations and therefore the IP address and gateway changed. I logged in and ran a script that the ISP had sent me years back when I set it up originally. Of course, I substituted the new info into the script. Before running the script I performed a write erase.

Upon a reboot I am pretty sure I could telnet to the new IP address but I had a seperate firewall issue that prevented me from fully testing it.

Today I couldn't telnet so I connected direct serial and it says that NVRAM is invalid, possibly because of a write erase. The boot sequence ends with a prompt to enter the initial configuration. However at this point I can't type anything. I can't say no or even hit enter for the default yes. I have tried Hyperterm from Win3.1, Win2000, and COM 7.5 (a shareware terminal).

I have also tried to perform the break sequence upon initially starting it and that does not work either.

Any ideas?

Please email me at

Thank you,


New Member

Re: need help configuring 2500 series

The Invalid NVRAM message is because of the write erase. After you finished configuring the router, you needed to do a WRITE MEM or COPY RUN START.

As far as the console goes, verify that handshaking is either software or turned off. You may just have a bad cable.


New Member

Re: need help configuring 2500 series


To break the password in 2500 series, some times the normal break sequence does not work. The following sequence of steps worked for me, you can try it out.

1. Open an Hyperterminal Application in win95/98.

2. set Baud speed : 1200

Flow Control: None

3. Connect the com port of the Computer to the router's console port.

4. Power on the router.

5. Press "space bar" on the keyboard for some 15 seconds. Just press and release the space bar for this amount of time. The screen won't display anything but don't worry.

6. Close the hyperterminal application and again restart the application.

7. The settings for the hyperterminal are

Baud speed : 9600

Flow Control : Hardware

8. Now you will be in the rmon mode.

9. change the config register value with

o/r 0x2142

10. reload the router with " i " command.

Now this time you will not be asked any password, after configuring the router and building it into memory donot forget to use the command "config register 0x2102" command.

I hope this helps.

For any clarifications you can reach me at

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