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    Disable or prohibit routing between local subnets

    Scheduled Pinned Locked Moved Firewalling
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    • morgensternM Offline
      morgenstern
      last edited by

      I have two subnets going off a quad port Intel NIC.

      First one on the interface em0 is my main network 10.3.0.0/24

      Second one, mapped to the em3 is a freshly set up lab network 10.3.100.0/24

      I would like to prohibit any devices located on the main network from being able to access the resources on the lab one and vice versa.

      pfSense acts as a default gateway for the lab network but not as a DHCP server. DNS server addresses given to the devices on the lab network are public (google, etc.)

      Currently the only FW rule for the lab net is the automated anti-lockout one so no traffic should be allowed in. However I can ping a server located on the lab network from my PC on the main network.

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      • GrimsonG Offline
        Grimson Banned
        last edited by Grimson

        @morgenstern said in Disable or prohibit routing between local subnets:

        Currently the only FW rule for the lab net is the automated anti-lockout one so no traffic should be allowed in. However I can ping a server located on the lab network from my PC on the main network.

        Read up on how the firewall and states work.

        RTFM:
        https://docs.netgate.com/pfsense/en/latest/firewall/firewall-rule-basics.html
        https://docs.netgate.com/pfsense/en/latest/book/firewall/index.html

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        • morgensternM Offline
          morgenstern
          last edited by

          Sorry, but tl;dr.

          Is there an easy, (what to do) answer available rather than being pointed to an encyclopaedia?

          GrimsonG morgensternM 2 Replies Last reply Reply Quote 0
          • GrimsonG Offline
            Grimson Banned @morgenstern
            last edited by

            @morgenstern said in Disable or prohibit routing between local subnets:

            Is there an easy, (what to do) answer available rather than being pointed to an encyclopaedia?

            If you want to maintain your firewall right you need to understand how it works, so start reading.

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            • morgensternM Offline
              morgenstern @morgenstern
              last edited by

              @morgenstern said in Disable or prohibit routing between local subnets:

              Sorry, but tl;dr.

              Is there an easy, (what to do) answer available rather than being pointed to an encyclopaedia?

              BTW, I did try putting a deny any*any rule on the lab network but I can still ping it.

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              • johnpozJ Offline
                johnpoz LAYER 8 Global Moderator
                last edited by

                Rules are evaluated top down, first rule to trigger wins no other rules are evaluated on the interface that traffic enters the firewall from the network.

                If you want to block network/vlan A from talking to network/vlan B then the rule to deny that traffic would go on the interface A rules.

                TL;DR for the manual of how firewall rules work is not going to be a valid answer - sorry ;) If you do not understand how the rules work, then you will never be able to adjust them to how you want them..

                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 25.07 | Lab VMs 2.8, 25.07

                morgensternM 1 Reply Last reply Reply Quote 1
                • morgensternM Offline
                  morgenstern @johnpoz
                  last edited by

                  Rules are evaluated top down, first rule to trigger wins no other rules are evaluated on the interface that traffic enters the firewall from the network.

                  If you want to block network/vlan A from talking to network/vlan B then the rule to deny that traffic would go on the interface A rules.

                  I have put the below rule on the top of rule set for network 1 and killed all the existing connection states to the network 2.

                  0_1549904311840_pfsense.JPG

                  Yet, I can still ping a server located on the network 2 from my pc on the network 1.

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                  • morgensternM Offline
                    morgenstern
                    last edited by

                    Not to worry. Resolved now. Thanks all.

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                    • johnpozJ Offline
                      johnpoz LAYER 8 Global Moderator
                      last edited by

                      ping or (icmp) is not tcp/udp ;)

                      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 25.07 | Lab VMs 2.8, 25.07

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