Cisco 2811 rom monitor mode

Unanswered Question
Oct 24th, 2007
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My 2811 every so often after a power cycle just sits there with the SYS PWR LED flashing. A console shows the rommon> prompt. So it appears to be sitting in the rom monitor mode rather than booting up. If I power cycle again then it boots up fine. I am not quite sure why this happens at times. My only guess is that perhaps if I have a console cable connected to a PC that during the power cycle the console port somehow gets a break from the PCs serial port that puts it in rom monitor mode.

Any ideas as to why this may be happening?


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royalblues Wed, 10/24/2007 - 11:07
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Connecting a console cable would not be causing such issues.

I think its mainly because the router is not able to read the IOS from the flash and returning to rommon

Can you format the flash and upload a fresh IOS again and check?


Brian Meade Tue, 10/30/2007 - 14:53
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This is most likely cause by a config-register problem. Try entering this command:

Router(config)#config-register 0x2102

This will set the config-register back to the default 0x2102. This config-register will boot the first image file in flash after checking for boot commands in your startup-config.


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