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    Double NAT

    Scheduled Pinned Locked Moved NAT
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    • DerelictD
      Derelict LAYER 8 Netgate
      last edited by

      You do not need outbound rules with only 1 WAN/default gateway.  pfSense is stateful.

      Reworded: The default rules are all you need.

      What's the corresponding firewall rule on WAN?

      Chattanooga, Tennessee, USA
      A comprehensive network diagram is worth 10,000 words and 15 conference calls.
      DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
      Do Not Chat For Help! NO_WAN_EGRESS(TM)

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      • O
        Ofloo
        last edited by

        Euhm, I allow all traffic there's no rules needed, I guess I don't filter anything at this point.

        Edit:

        I need to verify something, .. maybe I thought of the reason, .. but not sure if this could be the cause. As  i said I have 2 pfsenses

        WAN => pfsense1 => 192.168.1.1/24
        WAN => pfsense2 => 192.168.1.2/24

        the pfsense1 does nat on that range and pfsense2 as well is and forwards traffic to the same range is that possible.

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        • DerelictD
          Derelict LAYER 8 Netgate
          last edited by

          No rules means no connections allowed into WAN.

          Chattanooga, Tennessee, USA
          A comprehensive network diagram is worth 10,000 words and 15 conference calls.
          DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
          Do Not Chat For Help! NO_WAN_EGRESS(TM)

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          • O
            Ofloo
            last edited by

            No I have rules but allow any.

            IPv4 *	*	*	*	*	*	none
IPv6 *	*	*	*	*	*	none

            So I don't really see the point in adding an extra rule, that specifically allows that traffic, because allow any  should match all.

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            • DerelictD
              Derelict LAYER 8 Netgate
              last edited by

              No that's fine.  You'll have to figure out where the breakdown is then.  Check everything on the inside client (like its default gateway, firewall, etc.)

              Chattanooga, Tennessee, USA
              A comprehensive network diagram is worth 10,000 words and 15 conference calls.
              DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
              Do Not Chat For Help! NO_WAN_EGRESS(TM)

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              • O
                Ofloo
                last edited by

                ok the idea is to add a sip trunk and backup sip trunk to have one go over one wan and the other over an other wan

                so basicly i forward the port 5060 to 192.168.1.40 on both pfsense, the gateway for the 192.168.1.40 is 192.168.1.1, however on the pfsense1 box I have a rule that when it matches the target IP it should use the pfsense2 as gateway so this should be fine.

                pfsense1 forward 5060 to 192.168.1.40
                pfsense1 if target IP 91.213.251.136 and dport 5060 make it use gateway 192.168.1.2 otherwise gateway 192.168.1.1
                pfsense2 forward 5060 to 192.168.1.40

                and finaly on both the same nat rules as above. I can reach the traffic up until pfsense2, so if i remove the forward rule and setup nc to listen on 5060 i can connect to it and send and receive data, however for some reason it doesn't want to forward that traffic to the 192.168.1.40

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                • DerelictD
                  Derelict LAYER 8 Netgate
                  last edited by

                  I can't decipher that.  Draw a diagram.  See the one in my sig for the type of information you should include.

                  Chattanooga, Tennessee, USA
                  A comprehensive network diagram is worth 10,000 words and 15 conference calls.
                  DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
                  Do Not Chat For Help! NO_WAN_EGRESS(TM)

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                  • O
                    Ofloo
                    last edited by

                    I understand, .. can you recommend a unix/linux program to do so.

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                    • marcellocM
                      marcelloc
                      last edited by

                      Sip/rtp will not work with double nat. You will need a sip server or a sip and rtp proxy  on the firewall(or beside) to workaround it.

                      Treinamentos de Elite: http://sys-squad.com

                      Help a community developer! ;D

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                      • DerelictD
                        Derelict LAYER 8 Netgate
                        last edited by

                        It's hard enough with single NAT/PAT.

                        For future reference:

                        Free Diagramming Software: https://forum.pfsense.org/index.php?topic=1630.0

                        Chattanooga, Tennessee, USA
                        A comprehensive network diagram is worth 10,000 words and 15 conference calls.
                        DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
                        Do Not Chat For Help! NO_WAN_EGRESS(TM)

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                        • O
                          Ofloo
                          last edited by

                          That's the whole point SIP does work but it uses UDP, I wanted to give clients access to it using TCP cause in some networks UDP can't get passed a proxy, you need TCP but sip does work when it's using UDP it uses the same rules as TCP but for some reason TCP doesn't work.

                          And I have a sip server

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                          • johnpozJ
                            johnpoz LAYER 8 Global Moderator
                            last edited by

                            "You do not need outbound rules with only 1 WAN/default gateway.  pfSense is stateful."

                            Agreed.. But from his first few statements..
                            "I've got a second cable modem with isp setup the isp for some reason doesn't want to provide bridge"

                            But seems he using a different copy of pfsense, which is my bad for not reading it correctly.  But which is why I asked if 2 wan connections.
                            "You have 2 wan connections right.."
                            " What wan connection will it go out of - the normal wan, or this new double nat wan?"
                            "If your traffic comes in in isp 2, and you send out the traffic in answer out isp 1?"

                            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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                            • O
                              Ofloo
                              last edited by

                              double, still working on that network map, have it ready in a bit

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                              • O
                                Ofloo
                                last edited by

                                sorry not really good in these drawings tried to be as clear as possible

                                network.png
                                WAN2.png
                                WAN2.png_thumb
                                network.png_thumb

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                                • M
                                  mikeisfly
                                  last edited by

                                  What ISP are you using, I may be able to help? Why not put your firewall in the DMZ of the ISP NAT device. Most of the time their DMZ will forward all unsolicited traffic to the DMZ IP.

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                                  • O
                                    Ofloo
                                    last edited by

                                    The ISP nat is in dmz to 192.168.10.10, .. the target is the router, ..

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                                    • DerelictD
                                      Derelict LAYER 8 Netgate
                                      last edited by

                                      Aren't we just wasting time trying to double-NAT SIP?

                                      Chattanooga, Tennessee, USA
                                      A comprehensive network diagram is worth 10,000 words and 15 conference calls.
                                      DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
                                      Do Not Chat For Help! NO_WAN_EGRESS(TM)

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                                      • M
                                        mikeisfly
                                        last edited by

                                        Who is your ISP?

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                                        • O
                                          Ofloo
                                          last edited by

                                          The ISP with the issue is Telenet it's european, .. and no where not wasting time trying to make sip work, sip already works it uses udp. I'm trying to forward a tcp port, with netcat listening on the end, if you want I can make it port 10000, but i don't think this will change the issue, .. why is portforward not working i think it's strange. It shouldn't matter if the traffic before it is NAT it has dmz all is forwarded, .. so why does the traffic stop at the 192.168.10.10 IP

                                          If I setup netcat on IP 192.168.10.10, then I can connect to it, then if I forward the port, it can't connect, I'm pretty sure it's some configuration issue. But I wouldn't know where to start.

                                          # sysctl -a | grep forward
kern.smp.forward_signal_enabled: 1
net.inet.ip.forwarding: 1
net.inet.ip.fastforwarding: 0
net.inet6.ip6.forwarding: 1
# 

                                          nat on vr0 inet from 127.0.0.0/8 to any port = isakmp -> 192.168.10.10 static-port
nat on vr0 inet from 127.0.0.0/8 to any -> 192.168.10.10 port 1024:65535
nat on vr0 inet from 172.16.1.0/24 to any port = isakmp -> 192.168.10.10 static-port
nat on vr0 inet from 172.16.1.0/24 to any -> 192.168.10.10 port 1024:65535
nat on vr0 inet from 192.168.1.0/24 to any port = isakmp -> 192.168.10.10 static-port
nat on vr0 inet from 192.168.1.0/24 to any -> 192.168.10.10 port 1024:65535
rdr on vr0 inet proto tcp from any to 192.168.10.10 port = 5060 -> 192.168.1.40
rdr on vr0 inet proto udp from any to 192.168.10.10 port = 5060 -> 192.168.1.40
rdr on vr1 inet proto tcp from any to 192.168.10.10 port = 5060 tag PFREFLECT -> 127.0.0.1 port 19000
rdr on vr1 inet proto udp from any to 192.168.10.10 port = 5060 tag PFREFLECT -> 127.0.0.1 port 19000

                                          also i can connect to the ssh pfsense from the outside, however I can't forward it to any other ssh

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                                          • O
                                            Ofloo
                                            last edited by

                                            I think I know what the problem is, .. however I'm not sure how to solve this

                                            from what i gather

                                            tcp:

                                            SYN =>
<= SYN ACK
ACK =>
connection established

                                            however, ..

                                            WAN2 is a secundairy gateway while WAN1 is the default gateway, .. traffic is comming in through WAN2, however since the WAN1 is the default gateway of the client, it responds through WAN1, connection failed.

                                            Exactly like johnpoz said earlier.

                                            edit:

                                            yes, if i change the route for that specific ip i can connect to the tcp, however now my question how can i make a dynamic route so that when I connect to it that traffic goes through the correct gateway. And that's why UDP works. It all makes sense now.

                                            can this be solved with a routing daemon?

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