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Release Router MAC Lock on Comcast DHCP server

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Contributor

Release Router MAC Lock on Comcast DHCP server

Community,

 

I am in the process of upgrading my home router from a Cisco 1941 to a Cisco ISR 4351.  The Comcast DHCP servers will not give a DHCP address to my newer ISR 4351.

 

In searching Google and Forum posts I have arrived at the conclusion that the Comcast DHCP server holds a 'lock' on the MAC address of the existing router and will not release that lock for an unspecified number of hours or even days.  I am using an Arris TG1682 in bridge mode as my Cable Modem.

 

Who do I contact within Comcast technical support to get this lock released?  I really don't relish the idea of having my internet connection down for days in order for the lock to age out and release.

 

Thanks.

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Expert

Re: Release Router MAC Lock on Comcast DHCP server

Try power cycling the 1682. In bridge mode, it has a built in MAC addy cache that needs to be cleared.



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Contributor

Re: Release Router MAC Lock on Comcast DHCP server

EG,

 

Tried that already, in fact I have tried many different things over the past week and nothing has worked.

 

1.   Power cycled TG1682 with new router attached.  No DHCP address given by Comcast

2.  Left TG1682 powered off for one hour.  No DHCP address given by Comcast DHCP server.

3.  Left TG1682 powered off for two hours.  No DHCP address given by Comcast DHCP server.

4.  Factory reset TG1682, switched it into bridge mode.  Gives DHCP address to old 1941 router, but still no DHCP address from Comcast DHCP server for new ISR 4351.

 

I need to find someone in Comcast technical support (probably level 2 or higher) that knows how to clear the MAC lock from their DHCP server.

 

Thanks for the suggestion.  Already went down that path.

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Expert

Re: Release Router MAC Lock on Comcast DHCP server

Hmmmm.... I can't speak authoritatively as I am not am employee, but a don't think that their DHCP servers do a MAC addy "lock" on the LAN device that is hung off of a modem. That function is typically performed by a straight cable modem's MAC addy caching function. I could be wrong. I wish you good luck with it ! 



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Contributor

Re: Release Router MAC Lock on Comcast DHCP server

EG,

 

Thanks.  I was thinking that the Cable Modem might carry the lock, so that is why I factory reset it.  But even that did not work.  The problem is I don't know how to get the higher level technical support I need.  The tier 1 support personnel have no idea what I am talking about.

 

Any suggestions on navigating Comcast customer support?

 

Thanks.

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Frequent Visitor

Re: Release Router MAC Lock on Comcast DHCP server

Did you ever find a solution? I seem to be stuck in the same boat.
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Expert

Re: Release Router MAC Lock on Comcast DHCP server

@tzonkov 

 

Please create a new topic of your own here on this board detailing your issue. Dead thread now being closed.



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