Cisco 2800 auto-mdix or not?

Unanswered Question
Apr 19th, 2007

Similarly to

I have a Cisco 2811 connected to a hdsl-modem on the fastethernet0/0 and it doesn't matter what type of cable I use (straight or crossover).

But after an ios-update it works only with a cross-over cable.

Is it possible that it depends on the ios-version or type?

I am not able to find anything in the data sheets.

Thanks for help.


I have this problem too.
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Richard Burts Thu, 04/19/2007 - 08:13


I do not know the authoritative answer to this question. I thought that auto-mdix was a feature of the platform. If it stopped working when you did an IOS upgrade then it sure looks like you have demonstrated that it is release dependent behavior. Perhaps some of the Cisco folks in the forum can shed some light on this.



mig Thu, 04/19/2007 - 22:49


thanks for your statement.

Maybe for better understanding:

oldIOS c2800nm-ipbase-mz.124-2.XA

newIOS c2800nm-ipbasek9-mz.124-10


atlewis9777 Wed, 11/13/2013 - 10:02


   Did you ever find out why this happened.  This same thing happened to me.  I was running a 2811 with 12.4.19 IOS image with a straight through cable and then upgraded to 12.4.24.T8 and now it is requiring a cross over cable to bring that same link back up.


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