Upgrading the IOS on Cisco router 871W

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Apr 5th, 2008
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I am trying to upgrade the IOS on my Cisco 871w. I have the enterprise IOS which required me to upgrade the flash. Well since I swapped out the flash the router is booting up to the ROMMON prompt. How do I get the new IOS on to the router?



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kmccourt Sun, 04/06/2008 - 00:34
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Format the new flash and use the ROMMON tftpdnld command to download the new IOS image from a tftp server.

Essentially, you have to set the variables below and download via FE0, for example:

rommon 1 >IP_ADDRESS=

rommon 2 >IP_SUBNET_MASK=


rommon 4 >TFTP_SERVER=

rommon 5 >TFTP_FILE=c870-advipservicesk9-mz.124-15.T4.bin

rommon 6 >tftpdnld

Full instructions are at http://www.cisco.com/en/US/docs/routers/access/800/850/software/configuration/guide/rommon.html

timt976 Sun, 04/06/2008 - 10:47
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rommon 2 > ip_address=

rommon 3 > ip_subnet_mask=

rommon 4 > default_gateway=

rommon 5 > tftp_server=

rommon 6 > tftp_file=c870-advipservicesk9-mz.124-15.XY2.bin

rommon 7 > tftpdnld

Missing or illegal ip address for variable IP_ADDRESS

Illegal IP address

I enter all the commands but I am still getting that error. Is there something else I need to do first? Like change the config register.

Richard Burts Sun, 04/06/2008 - 11:24
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Try it again and this time put the commands into upper case rahter than lower case.




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