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Cisco 4500 IOS upgrade problems

I've got 2x Cisco 4500 routers in my lab.

They are based on identical HW, and I've decided to upgrade the IOS.

The first box went very well, where for the second one something didn't work.

Now when I boot it up goes directly into rommon.

I found a document telling how to set the system variables to be able to access a TFTP server. So I set the variables:






Now, following the procedure I suppose to use a command called "tftpdnld" but this is not present from my version of rommon.

The only command I can see is called dnld but I guess it doesn't do the same job.

Any advice on how to boot up this box?

May be copying the IOS with xmodem?

Thanks in advance


Re: Cisco 4500 IOS upgrade problems

Hi Bell,

Are you sure that there is no image in the flash. As you said you tried upgrading and something went wrong.

If there is no image at all in flash then we can go for xmodem but incase there is any image in router flash we can manually boot the router from the flahs with that image and once the router is up we can se the boot path and the ocnfig register vlaue to 2102.



Re: Cisco 4500 IOS upgrade problems


The switch is going into ROMMON mode because it cannot find a valid software image, its NVRAM configuration is corrupted or the configuration register is set to enter ROMMON mode.

To boot up this switch, follow the steps here:

Otherwise for information on how to copy Images from a Server to Flash using TFTP, RCP or FTP, go here and information on troubleshooting image transfer using TFTP or an RCP server is available here:

Good luck!


New Member

Re: Cisco 4500 IOS upgrade problems

Josef, thanks for your links, however the first one referes to a catalyas 4500 (switch) where I've got a router.

The second and third one refere on how to boot from tftp but from a working IOS, which I don't have :-(

The only command mentioned is rommon is xmodembut this is not available in the version of rommon my router runs.

Any other idea?

Thanks to everybody for the effort


New Member

Re: Cisco 4500 IOS upgrade problems

Here is the list of commands availables:

alias set and display aliases command

boot boot up an external process

break set/show/clear the breakpoint

confreg configuration register utility

cont continue executing a downloaded image

context display the context of a loaded image

cookie display contents of cookie PROM in hex

dev list the device table

dir list files in file system

dis disassemble instruction stream

dnld serial download a program module

frame print out a selected stack frame

help monitor builtin command help

history monitor command history

meminfo main memory information

repeat repeat a monitor command

reset system reset

set set a monitor variable

stack produce a stack trace

sync write monitor environment to NVRAM

sysret print out info from last system return

unalias unset an alias

unset unset a monitor variable

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