Cisco 870 Flash Upgrade

Posted on 2009-12-24
Last Modified: 2012-05-08
Hi Experts
I have a Cisco 871W ISR and I purchased 32meg of flash to replace the standard 4meg chip that came with my router.  The router has 20meg onboard flash anyway so I knew that removing the additional 4meg chip would effectively cause the router to boot into ROMmon mode (which it did)  My problem is this.
I seem to be unable to boot into router boot mode  "Router (boot)" after changing the conf register to 0x2101
The router continually boots with the following message regardless how I set the conf register

System Bootstrap, Version 12.3(8r)YI4, RELEASE SOFTWARE
Technical Support:
Copyright (c) 2006 by cisco Systems, Inc.

C870 series (Board ID: 3-148) platform with 131072 Kbytes of main memory

No bootable image file: flash:/
Unable to open boot file

rommon 1 >

The contents on flash is as follows

rommon 1 > dir flash:
Directory of flash:/

4    -rwx  931840    <date>               es.tar
5    -rwx  1505280   <date>               common.tar
6    -rwx  1038      <date>               home.shtml
7    -rwx  112640    <date>               home.tar
8    -rwx  2242560   <date>               wlanui.tar
9    -rwx  660       <date>               vlan.dat

47583232 bytes available (4800512 bytes used)

as you can see there is no IOS image or cfg file

If I go through the motion of setting an ip address on the machine using the IP_ADDRESS command it accepts it but the TFTP transfer times out.  
Do I need to set the ip address on one of the switchport interfaces like I would expect to do in router boot mode, the 871 has a 4 port switch built into it and Im not exactly sure what ethernet port it would use (suffice to say I have tried them all)

any help would be much appreciated, I'm sure Im missing out something very simple

Question by:paulbelsham
    LVL 34

    Expert Comment

    by:Istvan Kalmar
    Hi, firts of all you need to set confreg to 0x2102, after format the flash and copy the new ios to flash!

    Author Comment

    Thats done.  I only set it to 0x2101 to be able to get into Router (boot) mode so I could configure IP's on an interface.  How would I copy the IOS up to the router ?  I attempted to use xmodem but to copy a 20meg ios image would take a very long time.

    rommon 1 > confreg

               Configuration Summary
       (Virtual Configuration Register: 0x2102)
    enabled are:
    load rom after netboot fails
    console baud: 9600
    boot: image specified by the boot system commands
          or default to: cisco2-

    do you wish to change the configuration? y/n  [n]:  n
    LVL 34

    Expert Comment

    by:Istvan Kalmar
    you able to set higher speed the console and it is tranfering faster,,,

    Author Comment

    According to cisco you can only do that on 1600 series router.

    i'm getting my info from here

    If I type xmodem in I get these available switches

    rommon 2 > xmodem
    usage: xmodem [-cyrxu] <destination filename>
    -c  CRC-16
    -y  ymodem-batch protocol
    -r  copy image to dram for launch
    -x  do not launch on download completion
    -u  upgrade ROMMON, System will reboot after upgrade
    rommon 3 >

    Accepted Solution

    I knew it would be something stupid - WINDOWS FIREWALL was blocking the TFTP transfer even though I thought I had opened up an acception for it.

    I basically pasted this config into rommon and the image loaded

    tftpdnld -r

    Just one other thing though.  could you tell me how to save the image to Flash, it seems whenever the router is reloaded it boots back to rommon

    LVL 34

    Expert Comment

    by:Istvan Kalmar

    If the tftp blocking on your firewall the only way to us xmodem:

    rommon 2 > xmodem -c c870-advipservicesk9-mz.124-24.T1.bin

    Author Comment

    Hi _alias99
    I managed to figure out the issue myself in the end as windows firewall was the culprit.  I did ask a question at the end of my last post which was

    "Just one other thing though.  could you tell me how to save the image to Flash, it seems whenever the router is reloaded it boots back to rommon"

    but iklamars response wasn't really helpful with respect to that question.  I'll happily accept the experts solution if it would be easier for all concerned.

    Please advise

    Author Comment

    Hello DropBearMod
    I have already selected post number 26120940 which was submitted by me as the solution to the problem and an objection was raised, I dont know what the objection was though.  I posted my solution to solve the problem as well as I figured in future people might benefit from seeing the commands and knowing that temporarily disabling firewall software would be a prudent course of action if you were experiencing similar problems to mine

    I assume iklamar raised the objection as he was the only person to post on this thread, I'd be interested to hear his take on things.  I appreciate him responding to me but I dont feel he aided me in solving the problem.  I'm not really sure what to do for the best.
    LVL 34

    Expert Comment

    by:Istvan Kalmar
    ok I wrote my opinion sorry.....

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