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Router's configuration changes to a static ip

Hello - this is my first post on this site. 

We have a recurring issue at multiple sites across 2 router platforms where the router, whose WAN is configured for dhcp  will pick up a static ip in it's configuration which will kill the internet connection.  Reloading the router doesn't set it back to dhcp, implying that the startup-configuration has been altered as well as the running-config.   Local site personnel will then have to connect a single device to the modem so that we can remote in, console the router and remove the static ip information from router's configuration and reboot the router to restore the connection.  

The router's flash does not show any crash files associated with these incidents. 

Cisco IOS Software, 2800 Software (C2800NM-ADVIPSERVICESK9-M), Version 12.4(24)T2, RELEASE SOFTWARE (fc2)

the 2nd and less commonly effected router is

Cisco IOS Software, C880 Software (C880VOICE-UNIVERSALK9-M), Version 15.2(1)T1, RELEASE SOFTWARE (fc1)

We're looking for other commonalities such as modem make/model, provider, etc., but as of yet, have none.   Though this is a very uncommon occurrence, it is costly since it takes several hours to try to resolve the issue remotely. 

Have you ever heard of this happening?  

Any assistance is greatly appreciated. 


Router's configuration changes to a static ip


I'm going to ask the obvious. When you change the configuration back to dhcp, are you saving changes? I've never seen this before (although, I'm not saying it's not happening/possible). Generally, someone has to get in, make the change from dhcp to static on the interface, and because you're saying that the changes don't revert after a reboot, save the changes.

If that was the case, someone would need to be connected to the lan side in order to still have connectivity to the router long enough to save those changes. Do you have logging enabled on the router? Have you looked at when the last save to nvram was when this happens? (When you do a "show run" it will be the first couple of lines.)

As a precaution, I would change the enable passwords on the device to make sure no one has it and see if your issue goes away.



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HTH, John *** Please rate all useful posts ***
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