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1847 Views 6 Replies Latest reply: Mar 14, 2011 9:58 PM by Adam McDonald RSS

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IP Phone IOS

Feb 15, 2011 8:38 AM

Leonardo 31 posts since
May 20, 2009

Hello all,

      is there a way to erase the IOS in my cisco 7911G and then load in a fresh copy of IOS? 

  • Vinchhi 181 posts since
    Aug 6, 2010
    Currently Being Moderated
    1. Feb 15, 2011 4:05 PM (in response to Leonardo)
    Re: IP Phone IOS



    You can either upgrade your firmware to a newer version or restore your phone to factory settings. These are the only 2 options you've got.


    Is there a reason why you want to erase n reload the firmware? Are you facing any problems with the phone?



  • Vinchhi 181 posts since
    Aug 6, 2010
    Currently Being Moderated
    4. Feb 17, 2011 1:20 PM (in response to Leonardo)
    Re: IP Phone IOS

    Well, I am not aware if there about specifics of the upgrade from 7.2 to 8.5. However, the best place i would go for is the release notes.


    Let me know how it goes. I will learn from your issue.

  •  IOScertsGoneMad  105 posts since
    Apr 30, 2010
    Currently Being Moderated
    5. Mar 1, 2011 5:02 PM (in response to Leonardo)
    Re: IP Phone IOS

    I agree with Vinci, those are your two options.


    I have had a nearly identical problem, using 7940 phones and CME on a 2811 router.


    I'll try to look up old reference material for my solution.  If I recall, it had something to do with firmware versions causing an issue.

  • Adam McDonald 22 posts since
    Nov 1, 2010
    Currently Being Moderated
    6. Mar 14, 2011 9:58 PM (in response to Leonardo)
    Re: IP Phone IOS

    Your phone is probably rejecting the higher version phone load due to an authentication fail. I've worked with some phone upgrade shortcuts in the past, but in the end you should upgrade your phone firmware one step at a time (i.e. 8-3-2s, upgrade to 8-4 and then 8-5). I also must point out that you must change the term.default file with each firmware version. I’ve seen some people that think they can upgrade without uploading the new term file. The term file tells the phone the names and order to load the firmware files being served up via tftp.

    Issue these commands and yes I’d recommend capturing the output to a file for review.

    debug tftp events

    Terminal monitoring

    Then restart the phone and watch the messages. The fastest way to reset a phone is settings key **#**

    Watch the phone load and file transfer process. I wish there was an easier way… I get frustrated each time I forget and mail a new phone out and it turns up with an 8-3-2s phone load.

    In addition to file type, you’ll need to watch your file loads for file extension. I’ve noticed some loads out there that require a .loads extension and some that do not. Even more frustration, some 7916 and 7914 modules will vary on needing a .SBN or not under the load command depending on what phone firmware revision you’re attempting to use.



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