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LAN IP change

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New Poster

LAN IP change

I have an Arris SB8200. it works fine with my comcast internet. but the default LAN is 192.168.1.X.

I would like to change the LAN IP to work in my existing LAN. I would also like to turn off DHCP on the SB8200. it seems that comcast locks out configuration changes once the modem was activated.

Is there a way for me to change the LAN settings of the SB8200. or is there a Netgear/Motorola model that will let me customize the LAN side of my network?

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Expert

Re: LAN IP change

The 8200 is a straight cable modem / layer 2 bridge. You can't change the IP range. That's done in a router, as is the DHCP function. The 8200 doesn't do DHCP.



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New Poster

Re: LAN IP change

it must do a limited dhcp, because my laptop obtained an ip address. Any recommedations on a comcast compatible router that I can customize LAN settings?

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Expert

Re: LAN IP change

You don't believe me ?? The IP address is your WAN / public IP that gets assigned by the Comcast DHCP server / system. The 8200 simply bridges it across to the LAN device / client that is connected to the 8200 modem.



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Expert

Re: LAN IP change

You don't believe me ?? The IP address is your WAN / public IP that gets assigned by the Comcast DHCP server / system. The 8200 simply bridges it across to the LAN device / client / computer that is connected to the 8200 modem.



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New Poster

Re: LAN IP change

Strange, I rebooted my pc, and now the SB8200 is acting like a bridge. I obtained a routable IP. the 192.168.1.1 must be used for management on the SB8200. Now it makes sense. thanks for the quick reply.

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Expert

Re: LAN IP change


@Riley87 wrote:

I obtained a routable IP. the 192.168.1.1 must be used for management on the SB8200. Now it makes sense. 


FWIW, that address is a private / non-routable one.



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Gold Problem Solver

Re: LAN IP change


@Riley87 wrote: ... Arris SB8200 ... default LAN is 192.168.1.X ...

Modems supply private addresses in this range only when not yet in sync with Comcast's network. As soon as the modem is in sync it passes config requests to Comcast's DHCP server which supplies your routable/public IP.

 

If the modem was just powered on or rebooted, perhaps the LAN device made its DHCP request before the modem had time to achieve network sync.