7 Replies Latest reply: Apr 24, 2014 8:55 AM by Mark RSS

    How to use Xmodem to upload IOS

    Bilal Ahmed

      Hi all,


      I want to up ios for CISCO 1841 using hyperterminal. How can i do this using Xmodem file transfer.

      Please do the needful.





        • 1. Re: How to use Xmodem to upload IOS



          I assume you have to restore the IOS in flash.


          I haven't used XMODEM for a long time - I remember it was used for those Cisco devices without ROM-IOS like the 36xx and some of the older models of Catalyst switches. XMODEM was available (only) through monitor mode (e.g. interrupt boot process) via a ROMmon command resp. menu option.





          If you have physical access to the 18xx in question use the tftp option via ROMmon and a crossover-cable.


          I'm afraid there is no other option.


          Hope that helps.

          • 2. Re: How to use Xmodem to upload IOS

            Don't have much time to go step by step in deep details, so I will give you a short explaination and if isn't enough I will update you later.



            Open hyperterminal and after you set the COM port right click on the terminal window and select send file and select the IOS you want to load ( so the hyperterminal knows the path already)



            Now if you are in this prompt  router : , type


            copy xmodem: flash:( IOS name),then you will have following promt


            Begin the Xmodem or Xmodem-1K transfer now...


            before the 3 CCC appear quick right click on the hyperterminal window and choose Transfer > Send File.


            Choose the Xmodem protocol in the Send File dialog box and click Browse in order to select the Cisco IOS image (.bin file) that you selected previously.



            Click Send in order to begin the Xmodem transfer.



            Boot the new image that you just copied over  with the Xmodem procedure.



            Type boot flash:filename command


            Hope this help




            • 3. Re: How to use Xmodem to upload IOS

              The command lookup tool says the following about copy xmodem::


              copy xmodem:

              To copy a Cisco IOS image from a local or remote computer (such as a PC, Macintosh, or UNIX workstation) to Flash memory on a Cisco 3600 series router using the Xmodem protocol, use the copy xmodem: command in EXEC mode.

              Command History

              11.2 P  This command was introduced.

              12.2(15)T This command is no longer supported in Cisco IOS Mainline or Technology-based (T) releases. It may continue to appear in Cisco IOS 12.2S-family releases.

              12.2(33)SRA This command was integrated into Cisco IOS Release 12.2(33)SRA.


              and further:


              Usage Guidelines

              This command is a form of the copy command. The copy xmodem: and copy xmodem commands are identical. See the description of the copy command for more information.


              I'm curious whether it really works on a 18xx router - I don't have one at hand...

              • 4. Re: How to use Xmodem to upload IOS
                Scott Morris - CCDE/4xCCIE/2xJNCIE

                While you have all your fun uploading via the console port, I would recommend two things...


                1.  Put your console speed (baud rate) up as high as possible.  On a 1841, I believe that's 115200 bps.  Which is obviously faster than 9600 bps.


                2.  Use the "-y" option for Ymodem-G.  Other than some differences in error correction over Xmodem, you'll also get the benefit of pausing only once every 1,024 bytes (for ACK) unlike Xmodem which pauses every 128 bytes.


                it'll go MUCH faster with those two things.





                • 5. Re: How to use Xmodem to upload IOS
                  Bilal Ahmed

                  Thanks for your comments.

                  I tried to increase baudrate but it is not working over 9600

                  also i tried X modem to copy ios, it almost takes 9 hours to copy the ios image ,

                  But after that same problem is happning again.

                  attached herewith are images of procedure which i followed ,hope it will help you understanding my problem.

                  • 6. Re: How to use Xmodem to upload IOS

                    set BAOD 115200  +  hyperterminal 115200 - reload

                    • 7. Re: How to use Xmodem to upload IOS

                      If you are practicing xmodem then you should look to changing your speeds like suggested above.  use the -s option to set a higher speed and make sure that you have enough room for new image.


                      If this is not a test and you really need to put the new image on your router xmodem would be my last choice.  It is an 1841 so there should hopefully be a compact flash which you can use a memory card ready to drag and drop the new image onto.  The next option would be to use the tftpdnld option from ROMMON where you can use the FastE or GigE ports of the router.