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    Double NAT

    Scheduled Pinned Locked Moved NAT
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    • O
      Ofloo
      last edited by

      actually I've got 4 connections and 2 pfsenses, .. the thing is one of 2 works kinda, it has also nat issues, with your post this makes sense, however the new pfsesne has is new and has only one wan for now, .. the point is that it is behind a nat enabled modem, I can't disable it since it's the isp who delivers it like this, ..

      However I can setup portforwarding and dmz, which I did, on the new pfsense the one I'm having issues with, .. I can make a port listen nc -l 5060 for example and connect to it from the internet, however once i setup portforwarding on the pfsense box it self to forward that traffic to a IP within the lan it doesn't work.

      so basicly I can connect to the port however once I want to forward it, it doesn't work. So i think something is wrong in the NAT of the new pfsense, …

      so basicly this pfsense has wan IP 192.168.10.10 and I need to forward some ports to 192.168.1.40 all the traffic arrives only at the point of portforwarding it all goes wrong but i can't wrap my head arround it why.

      This is a forward, what would the corresponding outbound rule be.

      WAN	TCP/UDP	*	*	WAN address	5060 (SIP)	192.168.1.40	5060 (SIP)

      I thought these where those rules

      WAN	 	192.168.1.0/24	*	*	500	WAN address	*	YES
WAN	 	192.168.1.0/24	*	*	*	WAN address	*	NO
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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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