In ROMMON mode, how to load IOS via TFTP?

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Apr 13th, 2005
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I did a successful Flash memory upgrade on my 2502, but when I tried copying the IOS from my 2501 it didnt' like it. "Wrong system software for this hardware" it keeps saying at bootup. So I send a break signal and get a rommon prompt, and it looks like I can set it up to take an IOS image via TFTP (I'm hoping the one on my other 2502 is good enough); but which commands/arguments do I use at the rommon prompt to make that happen?

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Overall Rating: 5 (2 ratings)
mhussein Wed, 04/13/2005 - 14:35
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From the rommon prompt boot into the built-in rx-boot image:

>o/r 0x2101


This should boot the rooter into the bare minimum rx-boot, and from there you can upgrade the image:


router(boot)#copy tftp flash

#continue with the copy procedure, verify file is copied

hostname(boot)#show flash

#reset the config register and reload

hostname(boot)#config t

hostname(boot)(config)#config-register 0x2102


See this doc:



CriscoSystems Wed, 04/13/2005 - 16:31
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Thank you; that did the trick.

(except I'm still kinda wondering about those tftp-related commands I saw listed in the 'help" output in rommon mode)

m.gaudion Fri, 04/22/2005 - 08:25
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I had to do this today on one of our 2851's.. rommon using the 'set' command and then going through setting up a local ip, and a tftp server ip/image name etc., then using 'tftpdnld' command

The cisco doc linked below was helpful;



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