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    DHCP relay issue

    Scheduled Pinned Locked Moved DHCP and DNS
    8 Posts 2 Posters 3.5k Views
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    • P
      pftest
      last edited by

      Hey guys, im trying to set up a network here with the pfsense server working with my dhcp server that already exists. I already tried using the dhcp relay for my LAN but it didnt work. Initially it works well when i test with the default ip in LAN but when i enable the dhcp relay to get the ip from my dhcp server it stops working.

      Something like that:

      Internet -> DHCP Server -> Pfsense Server -> Switch …

      There is any additional changes that i gotta do instead of only enable the dhcp relay on pfsense?

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      • johnpozJ
        johnpoz LAYER 8 Global Moderator
        last edited by

        So your dhcp server is on the wan side of your pfsense?  Normally you would use the dhcp relay to relay from multiple segments on your lan side to use dhcp server on one of your lan segments.  If on wan side I would assume your natting, this could be an issue.

        An intelligent man is sometimes forced to be drunk to spend time with his fools
        If you get confused: Listen to the Music Play
        Please don't Chat/PM me for help, unless mod related
        SG-4860 24.11 | Lab VMs 2.8, 24.11

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        • P
          pftest
          last edited by

          @johnpoz:

          So your dhcp server is on the wan side of your pfsense?  Normally you would use the dhcp relay to relay from multiple segments on your lan side to use dhcp server on one of your lan segments.  If on wan side I would assume your natting, this could be an issue.

          Thanks for reply.

          Yes, its on the wan side of pfsense server, is it an issue? I mean, there is any way to set up that natting im suggesting?

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          • johnpozJ
            johnpoz LAYER 8 Global Moderator
            last edited by

            Well yeah, I can't think of why you would ever set it up like that to be honest.  By default pfsense would be natting traffic from lan to wan.  Did you turn off natting and just using as firewall and router?

            What are you wanting to accomplish with pfsense in your setup, if your networks dchp server is on the wan side of pfsense?

            An intelligent man is sometimes forced to be drunk to spend time with his fools
            If you get confused: Listen to the Music Play
            Please don't Chat/PM me for help, unless mod related
            SG-4860 24.11 | Lab VMs 2.8, 24.11

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            • P
              pftest
              last edited by

              Well thanks again, im quite new on it but this topology that i showed is the one i thought would work  :P

              What would u suggest for me? The main point is having my dhcp server working with pfsense server, cuz right now my network has this dhcp server working fine, i just want to insert pfsense server to control the internet access with captive portal.

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              • johnpozJ
                johnpoz LAYER 8 Global Moderator
                last edited by

                well then your connection should be like this

                internet – pfsense -- switch -- all other devices including your dhcp server.

                An intelligent man is sometimes forced to be drunk to spend time with his fools
                If you get confused: Listen to the Music Play
                Please don't Chat/PM me for help, unless mod related
                SG-4860 24.11 | Lab VMs 2.8, 24.11

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                • P
                  pftest
                  last edited by

                  I see.. so the internet will be on wan side of pfsense? Ill do the tests and let u know the results.

                  i was a bit confused about the topology cuz i have my dhcp server combined with dns.

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                  • johnpozJ
                    johnpoz LAYER 8 Global Moderator
                    last edited by

                    Does your dhcp server also do NAT for your network, or route your other devices that are on public IPs?

                    pfsense is designed to be your networks gateway/firewall to the internet.  It can be used as just an internal router/bridge/firewall - but by default its going to expect your internet to be on its WAN, and then NAT all your devices to your public IP behind it.

                    I am guessing your dhcp and if it does dns that is maybe a AD DC?  If so it should be behind your gateway/firewall - and you can just have it forward its external dns to pfsense, or outside for public dns.  And all your internal clients would still use it for your internal AD dns, etc.

                    An intelligent man is sometimes forced to be drunk to spend time with his fools
                    If you get confused: Listen to the Music Play
                    Please don't Chat/PM me for help, unless mod related
                    SG-4860 24.11 | Lab VMs 2.8, 24.11

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