How to upload IOS from ROMmon?

stcstc Posts: 5Member ■□□□□□□□□□
Hi guys. I have a Cisco ADSL 837 router what stays in rommon. So I have to upload a new image. I have the image, router is connected with the console cable, I have Terminal up and running, but can't upload the image. I don't get it at the moment, can I do it with the console cable I should it be direct cable from my PC to the router? Where should I keep the image for the upload, becasue the following commands doesn't specify it?

tftpdnld -u

Thanks guys.


  • networker050184networker050184 Posts: 11,962Mod Mod
    You need to use xmodem in order to load the IOS over the console cable. Check out this link for information on loading an image through xmodem.
    An expert is a man who has made all the mistakes which can be made.
  • stcstc Posts: 5Member ■□□□□□□□□□
    Thanks for your reply. I did as said on the website:

    rommon 6 > xmodem c:\c837-k9o3syb-mz.124-17.bin
    Do not start the sending program yet...
    File size Checksum File name
    2789 bytes (0xae5) 0xbc1e conf

    WARNING: All existing data in bootflash will be lost!
    Invoke this application only for disaster recovery.
    Do you wish to continue? y/n [n]: y
    Ready to receive file c:c837-k9o3syb-mz.124-17.bin
    $$$$$$$$$$BB0BB0Download Complete!

    Timeout waiting for data - aborting download...
    rommon 7 >

    It seems it didn't download it properly?
  • livenliven Posts: 918Member
    Are you sure you have a valid IOS image?

    I have used xmodem many times and it usually works unless the device has a memory/storage issue or the image is bad.

    Also if memory serves me correctly you don't need to specify the path to the file on the xmodem command line.

    You specify the file location with the hyper terminal application after xmodem states it is ready to receive the file.
    encrypt the encryption, never mind my brain hurts.
  • georgemcgeorgemc Posts: 429Member
    What program are you using on you PC to do the XMODEM upload? Let's see a screen shot of how the upload goes on the PC side.

    WGU BS: Business - Information Technology Management
    Start Date: 01 October 2012
    QFT1,PFIT in progress.
  • APAAPA Posts: 959Member
    at rommon> prompt just type xmodem and press enter

    this will inform you to start sending the file through the following method.

    Then via whatever program you are using to console into the device... eg hyperterminal send the IOS image via the Transfer Menu's send File option.... This allows you to select the file/folder/path from where the xmodem protocol is to pull the IOS image down from...

    with Hyperterminal you actually have to choose the xmodem protocol from the protocol dropdown menu......

    remember you must enter xmodem on the device first then start sending the file before it times out.... Which is what you are experiencing... there is no need to specify the file location via the xmodem cmd at the IOS CLI...

    Starting a transfer via xmodem is the same way via Cisco IOS all the time but initiating the file transfer through your console software can differ..... If you could let us know what software you are using if it isn't hyperterminal we could be of greater assistance....for instance at work and home I tend to use SecureCRT...

    CCNA | CCNA:Security | CCNP | CCIP
  • APAAPA Posts: 959Member
    or you could always ****....... and use the tftpdnld cmd....

    but you will need to use cross-over cable between your PC and the router..... Make sure your PC has the IP address that is the address set as the tftp_server within ROMMON.... Download some tftp software (Pumpkin or Solarwinds TFTP server are the most popular)

    Run the tftp software on your PC ensure the IOS image file is in the folder that the TFTP software picks up it's files from.... then initiate the TFTP file transfer from the IOS CLI....

    Xmodem is only used to transfer files via the console cable.....

    CCNA | CCNA:Security | CCNP | CCIP
  • stcstc Posts: 5Member ■□□□□□□□□□
    I have Windows Vista, so had to install HyperTerminal by Hilgrave. If I type xmodem, I get this:
    rommon 1 > 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 2 >

    I don't get the prompt to start downloading a file.
    So I tried the command I tried before xmodem c:\filename.bin and then went to Transfer file and specified the location and started uploading. But time remaining is 3hours and 45 minutes :) IOS is about 9Mb
    Is that normal?
  • determinedgermandeterminedgerman Posts: 168Member
    x-modem upload is very slow...could be that long....even for 9MB......

    That's why you use x-modem only if you have no other choice.....
  • stcstc Posts: 5Member ■□□□□□□□□□
    I do have the cross-over cable. So does it go from my PC straight to the routers console port then? And I have to specify some details like those:
    ip_address= (router)
    default_gateway= (???)
    tftp_server= (PC)
    tftpdnld -u

    If the cable is between PC and the router, there is no default gateway then, is there? And I should use Pumpkin then, shouldn't I?
  • dtlokeedtlokee Posts: 2,381Member
    Increase the console speed to 115Kb/s, it will upload much faster that way, also use xmodem-1k

    Why can't you just use the tftpdnld command?
    The only easy day was yesterday!
  • APAAPA Posts: 959Member
    cross-over cable should not go into console port....

    It should go from your PC to the ethernet port on your router.....

    TFTPDNLD will save you so much more time!!! It took almost 45 mins for a really small switch IOS image to upload for me...and that's because I had no other option.....

    No need for default gateway.... both PC and router will be on the same subnet so all is good..... just leave the default-gateway settings in as it won't affect anything....

    CCNA | CCNA:Security | CCNP | CCIP
  • stcstc Posts: 5Member ■□□□□□□□□□
    Thanks guys.

    I never thought I can use 2 cables between the PC and the router to do different tasks (console and cross-over)
    So I got it solved, thanks again everybody
  • APAAPA Posts: 959Member
    glad we could assist :)

    CCNA | CCNA:Security | CCNP | CCIP
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