Cisco 1721 Wont Show command prompt

Posted on 2008-11-17
Last Modified: 2012-05-05
I have a cisco 1721 that wont show a command prompt, i need to get to the command prompt so I can reload a differnt IOS on.
When I power on the router I am faced with

C1700 platform with 65536 Kbytes of main memory

open: file "/c1700-k8o3sy-mz.122-6.bin" not found
open(): Open Error = -1
loadprog: error - on file open
boot: cannot load "flash:/c1700-k8o3sy-mz.122-6.bin"

System Bootstrap, Version 12.2(7r)XM2, RELEASE SOFTWARE (fc1)
TAC Support:
Copyright (c) 2003 by cisco Systems, Inc.
C1700 platform with 65536 Kbytes of main memory

program load complete, entry point: 0x80008000, size: 0x53c43c

Error : compressed image checksum is incorrect 0xA04C3FEE
        Expected a checksum of 0x89D1F786

*** System received a Software forced crash ***
signal= 0x17, code= 0x5, context= 0x0
PC = 0xbaddaddd, Vector = 0xbaddaddd, SP = 0xbaddaddd

*** Machine Check Exception ***
PC = 0xfff17450, Vector = 0x200, SP = 0x83fffe40

It goes no further, does anyone have any ideas of what I can do ?

Question by:Brenton_AUSTRALIA
    1 Comment
    LVL 2

    Accepted Solution


    You'll probably need to break into the router as it is booting up to get into what's called ROMMON mode.  As the router is booting, in your terminal program, start hitting the break key.  You should eventually end up at a rommon> prompt.

    From this prompt, you can verify the name of the IOS file in flash is the one that's actually being told to boot.  So do a rommon> dir flash: and that should list the contents of the flash: file system.

    You'll also be able to give the router an IP address in this mode so that you could transfer a new IOS image to it using a TFTP server in case the one on the router is corrupt.  You can do a rommon> del flash:iosname  where iosname is the name of the flash file in there.  That should delete that file from the flash: system and free up space for you to load a new image.

    Try this Cisco link for additonal ROMMON commands:

    Hope this helps!

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