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New Member

Help Cisco 831 Router Not Booting

I need help with a Cisco 831 I am trying to help somone else fix there mistake I do not have the exact command that was enterd when the IOS and ROM used to load properly but now when the you are connected to console of the router and u turn on the router a bunch of random symbols come on the screen and the console does not allow key strokes this is all before the IOS would load and which it doesn't and never comes up to the rom prompt and cannot break the boot up with ctrl+break and do not have the Ip address of the router yet and cannot tftp becuase of the absence of the rom prompt or any prompt for that matter how can it be rest or fixed so that I can get to the rom prompt to clean it up and reinstall the IOS

New Member

Re: Help Cisco 831 Router Not Booting

Try all baud rates with a reboot of the router:

1200, 2400, 4800, 9600, 19200, 38400, 57600, 115200.

When you can read the routers boot messages you know the baud is correct so break the boot sequence.

you should be at the rommon> prompt so type:

try this first (it might work)

confreg 0x2102

or this (i know this works)


which should show the existing config register then start some questions:

Answer the questions accordingly so that you correct the baud rate and ignore config at boot up.

lastly it will ask do you want to change config register setting ? enter no

you should be back at rommon>

type in


system will reboot

to router>

so type in:


conf t

conf 0x2102

copy the config off the router (for safe keeping)

reboot it

select no to save config changes

change your console baud to 9600

have fun

New Member

Re: Help Cisco 831 Router Not Booting

Thank You very much for the information all though This morning I cautally got ti working and u where correct the Baud Rate was set wrong as well as all connection settings but yeah got it going and have the IOS loading again like a cahmp I do appreciate your response even though I got it going u would have been a life saver for me thanks again

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