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    firewall without NAT

    General pfSense Questions
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    • O
      olivier demoustier
      last edited by

      Hi, is it possible to create a firewall without NAT? I would like to make something that blocks a range of ports, but all other traffic should pass unchanged. This system has no internet and no need of DHCP. Everything is on static IP's and 99% of the traffic is UDP.
      Any suggestions are more than welcome. Thx in advance

      KOMK 1 Reply Last reply Reply Quote 0
      • KOMK
        KOM @olivier demoustier
        last edited by

        @olivier-demoustier I've never tried it but turning off outbound NAT would do it? Firewall - NAT - Outbound. Set it to Disable Outbound NAT rule generation. I don't know if that removes or disables the existing rules or not.

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        • stephenw10S
          stephenw10 Netgate Administrator
          last edited by

          Yes, that would remove all outbound NAT rules.

          https://docs.netgate.com/pfsense/en/latest/nat/outbound.html#disabling-outbound-nat

          Steve

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          • O
            olivier demoustier @stephenw10
            last edited by

            @stephenw10 Thanks for all the quick responses. unfortunately it does not work for me.Screenshot 2021-05-22 191521.jpg
            Attached some screenshots: NAT disabled and No firewall rules. And still no UDP traffic passing tru floating.jpg wan.jpg lan.jpg
            I'm probably missing some more? I started with a fresh install, no VLANs
            I left the IP address for LAN at 192.168.1.1 (DHCP disabled)
            But what IP address should I set for WAN? Like I mentioned, in this system everything is on static addresses.
            Thanks in advance.

            KOMK 1 Reply Last reply Reply Quote 0
            • KOMK
              KOM @olivier demoustier
              last edited by KOM

              @olivier-demoustier You need at least one Allow rule on any interface whose clients need to go through that interface. Right now, you have it configured to block all traffic to WAN and LAN.

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              • O
                olivier demoustier @KOM
                last edited by

                @kom
                No luck :)
                1.jpg 2.jpg 3.jpg

                KOMK 1 Reply Last reply Reply Quote 0
                • KOMK
                  KOM @olivier demoustier
                  last edited by

                  @olivier-demoustier I have no idea what you're trying to do with which clients on whatever network so I can't really comment further other than to say that you need to do some reading on pfSense and how it works. Perhaps if you explained what you have and what you are trying to do, it would be more clear. In a lot of cases, new users decide on a course of action which is either wrong or sub-optimal and then ask specific questions when they should be describing what they want to achieve and then asking for suggestions on how to best do it.

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                  • O
                    olivier demoustier @KOM
                    last edited by

                    @kom
                    Hi Kom, I understand what you are saying. And indeed I'm not familiar with firewalls and NAT's.
                    In short the situation. Lighting desk that sends (a lot ) of UDP on port 6454 (artnet, broadcast) and some other UDP on port 9000 (OSC). I would like to split up this traffic with 2 firewall's. So I have 2 UTP cables. One with only the UDP on port 6454 and another with only the UDP on port 9000.

                    KOMK S 2 Replies Last reply Reply Quote 0
                    • KOMK
                      KOM @olivier demoustier
                      last edited by KOM

                      @olivier-demoustier What network is on WAN, and on LAN? How are these devices (I have no idea what a lighting desk is) connected to pfSense? IS this UDP traffic coming from one client or multiple clients? Why do you want to split that UDP traffic in the first place?

                      I have to leave until tomorrow so post your answers and maybe someone else can help you with this.

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                      • O
                        olivier demoustier @KOM
                        last edited by

                        @kom
                        A lighting desk is a console that controls lights for TV/rock shows....
                        It broadcasts "ARTNET" this is a UDP signal on port 6454. In large show's it reaches up to 80mb/sec. At the same time it receives other controls on port 9000 (called OSC). Sometimes the OSC gets lost by all the broadcast or/and the osc needs to be wireless via WIFI. If we don't split the ARTNET from The OSC, all the artnet slows down the wifi.
                        In real life it is a bit more complicated and also more different protocols involved. But if the simple setup works, I can adjust further.

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                        • V
                          viragomann @olivier demoustier
                          last edited by

                          @olivier-demoustier
                          Does all communication devices have fix IPs or do they use UPnP to connect to the other?

                          O 1 Reply Last reply Reply Quote 0
                          • O
                            olivier demoustier @viragomann
                            last edited by

                            @viragomann
                            All fixed IP's

                            V 1 Reply Last reply Reply Quote 0
                            • V
                              viragomann @olivier demoustier
                              last edited by

                              @olivier-demoustier
                              I can imagine that you get an asymmetric routing in this setup. If that's the case, it possibly helps to enable sloppy state handling.
                              You can do this in the firewall rules in the advanced options.

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                              • O
                                olivier demoustier @viragomann
                                last edited by

                                @viragomann
                                For the moment, I don't get any UDP packet true the firewall.

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                                • stephenw10S
                                  stephenw10 Netgate Administrator
                                  last edited by

                                  pfSense will route between the WAN and LAN interfaces. Traffic coming into the LAN will be routed out to the WAN as long as firewall rules pass it and a route exists. That could be the default route or between the WAN and LAN subnets directly.

                                  However, you're taking about broadcast traffic that will not be routed. That is always inside one subnet.

                                  What subnets do you have on WAN and LAN?

                                  What IPs are you testing between?

                                  It sounds a lot like you might actually want a bridge here with both interfaces in the same subnet.

                                  Steve

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                                  • S
                                    SundarNET 0 @olivier demoustier
                                    last edited by SundarNET 0

                                    @olivier-demoustier if you are trying to isolate traffic by having 2 nics in the lightbox then you need to isolate those IP addresses and use direct IP address rules in your firewall but possibly going to need to use NAT redirects for that
                                    I say this assuming you are trying to isolate one ports traffic through one NIC and the other via the second to stop overloads?

                                    O 1 Reply Last reply Reply Quote 0
                                    • AKEGECA
                                      AKEGEC
                                      last edited by

                                      Some people are still believing that NAT is evil. Just because some people don't like entering their home through a door instead a wide gate. By default a door denies all inbound.

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                                      • N
                                        NOCling
                                        last edited by

                                        If it is broadcast, use only a managed switch with different VLANs, then you got 2 broadcast domains and no interaction betwen this.

                                        One VLAN is used for WiFi and the other dont flod the WiFi anymore. You want now to route betwen this VLANs, you neet different IP Subnets and then you can use an Firewall between.

                                        Netgate 6100 & Netgate 2100

                                        O 2 Replies Last reply Reply Quote 0
                                        • O
                                          olivier demoustier @SundarNET 0
                                          last edited by

                                          @sundarnet-0
                                          Hi SundarNet, The lighting console has only 1 nic. So all this broadcast ( on port 6454 and 9000) passes in/out 1 nic on that end. This meaning , only 1 IP adress.

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                                          • O
                                            olivier demoustier @stephenw10
                                            last edited by

                                            @stephenw10 IP range is 2.x.x.x subnet 255.0.0.0

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