We have a monowall router behind DPC3941B, having trouble connecting to internet. Just purchased static IP and still can't get it to work. Comcast says everything looks good on their side. Modem is in Bridge Pass-through mode. On the monowall on WAN interface we tried entering static IP and gateway they gave us and still no go. Also, there is field for entering MAC address, I assume MAC address from the modem, we tried both of them as well.

If we connect desktop directly to the modem we get 169.x.x.x address not our static IP.

What else can we do to get it going?


1 Answer 1


Check you Netmask, it should probably be /30 (and I think monowall defaults* to /31). Comcast should have given you three numbers (well, not counting the two DNS servers):

  • Your usable IP address
  • The gateway IP
  • The Netmask to use

For single static IP accounts, this is usually (or /30). For reference, see http://www.subnet-calculator.com/cidr.php

Also, be sure to set the WAN Type drop-down to 'Static' in the monowall config page as it defaults to DHCP. Leave the rest of the fields blank, including MAC spoofing.

To talk to the Comcast router you'll need to put static IP info into the computer/laptop you're plugging in to it. By default, Comcast routers will not have DHCP running but should be listening on Change your computer from using DHCP to using a fixed IPv4 of and then plug into the Comcast box. You should then be able to open in a web browser and get the modem's login page.

*I haven't used monowall in ages, and could very well be wrong on this

  • Thank you for your help. It was exactly these things you mentioned that needed to be configured in order to work.
    – Shreko
    Dec 10, 2015 at 4:37

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.