Gateway Not Active when connecting to 4g comcast backup gateway

  • I have configure opt1 as a backup wan thru Comcast's 4g Backup router. The interface say's its up but the gateway status always says the gateway is down. I am using dhcp for this interface the Comcast router issues an address like as the dhcp address. The Interface sees the issued IP and interface status shows its being used by the interface. Now if I connect a laptop or desktop directly to the Comcast router they work correctly and have access to the internet thru this router using DHCP.
    If I move the Ethernet cable on PFSENSE router connected to opt1 to another modem it comes up and works correctly. Is there some option that must be set to allow the pfsense router to talk correctly to Comcast 4g router.
    I have replace the hardware etc. no joy. tried a different port, .....

    I am quite frustrated!

    Does anyone know of a solution to this issue/seen it before?

  • @ercoupeflyer

    Do you have a valid address configured for that router's monitor IP? You could try something like the Google DNS at

  • Netgate Administrator

    Yes, by default it will be using the 4G routers address which is probably (or maybe .254) but that does not necessarily have to respond to ping. Though I would expect it to.

    Setting an external IP to monitor there will give you a much better idea of the actual connection quality but it will also use data on the connection which can add up.


  • @JKnott
    Yes I Have configured , the gateway address and like etc and it makes no difference. the part i don't understand is if I configure the interface address to dhcp, the opt1 for example will get a valid ip address... but after that stops working

  • Netgate Administrator

    Run a packet capture on that interface. Do you see any traffic there at all?

    You should see at least the monitoring pings or pfSense ARPing for the gateway IP.

    Is the gateway supplied inside the subnet given by dhcp?


  • @stephenw10
    When I look at the stats for opt1, i can see it sends many out but receives none... Strange!

    It seems to be something to do with the gateway Comcast provided a Cradlepoint router for the 4g. If I connect opt1 to the Comcast modem router. it picks up an IP and works fine. I am wondering if its possible there is a problem with protocol versions etc. Any Thoughts?

    Let me try to do a capture.

  • Netgate Administrator

    I gives you a public IP or is the Cradlepoint routing/NATing?

    Check the gateway is gives you is inside the subnet is gives you. If not pfSense/FreeBSD will complain and not connect to it as that is invalid. Other OSes will ignore that and connect. There is a checkbox to force pfSense to use the invalid gateway if so.


  • Ok, The Comcast/modem/ router gives it an gives it an ip of 10.0.0.x, we also have passthru on this device for our fixed ip addresses. This connection works for opt1
    The cradlepoint router/nat gives it an ip of 192.168.165.x i have turned off the filters for local ip addresses.... this connection fails for opt1. If I connect a laptop to the cradlepoint it works just fine...