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    Mail servers imap behind pfsense not reachable

    Scheduled Pinned Locked Moved Firewalling
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    • chpalmerC
      chpalmer
      last edited by

      Do a packet capture on your LAN port while someone tries to connect from outside and see if the traffic shows up there or not.

      Triggering snowflakes one by one..
      Intel(R) Core(TM) i5-4590T CPU @ 2.00GHz on an M400 WG box.

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      • D
        daan
        last edited by

        This is what I get, 192.168.1.118 is my pc.
        12:44:52.525535 IP 192.168.1.118.39414 > MY.IP.00.00.143: tcp 0

        The capture is full with these packets, no incoming packets found..

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        • johnpozJ
          johnpoz LAYER 8 Global Moderator
          last edited by johnpoz

          @daan said in Mail servers imap behind pfsense not reachable:

          This is what I get, 192.168.1.118 is my pc.
          12:44:52.525535 IP 192.168.1.118.39414 > MY.IP.00.00.143: tcp 0

          Where Exactly are you sniffing for that? Sure isn't your wan of pfsens showing traffic getting to it.. Since the source is rfc1918, doesn't go over the internet.

          Step 1 in troubleshooting port forwarding is VALIDATION that traffic gets to wan of pfsense, pfsense can not forward something it never sees..

          Then validate it sends it on by sniffing on lan side of pfsense.. Here is example

          imap.png

          That is my wan... Here is sniff on lan side, showing sending to IP on inside.. And my machine sending back a RST

          rst.png

          After I setup a port forward.

          portforward.png

          Everything you need to troubleshoot port forwarding is here
          https://docs.netgate.com/pfsense/en/latest/troubleshooting/nat.html

          just use can you see me . org to send traffic from the outside.

          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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          • D
            daan
            last edited by

            When I check for open LAN ports on 192.168.1.200 (My mail server IP, running in docker) I get the expected output.
            67ba5462-6d0e-40ae-b795-0ad277009af9-image.png

            When I check for open ports on " https://www.yougetsignal.com/tools/open-ports/ " the imap and smtp ports are all reachable.

            And there is another weird thing, I have my mail setup on my phone. I do get notifications from my email app when I get a new mail (The title and part of the message is readable in the notification), but when I open the app the email is not there and it throws a IMAP connection error..

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            • johnpozJ
              johnpoz LAYER 8 Global Moderator
              last edited by johnpoz

              Dude I can not help you if you can not provide the simple info that would take you 10 seconds to provide.

              Do a sniff on pfsense wan... Not go to can you see me . org.. put in 143 - do you see the packets on pfsense? If so,

              Then sniff on the lan side and repeat the process.. If you see traffic going to your imap server rfc1918 IP.. Then pfsense has done its job.. .Whatever other issues you might be having nothing to do with the simple act of forwarding a port.

              I just hit the IP you used to connect to the forum and it is answers via 143

              Escape character is '^]'.
              * OK [CAPABILITY IMAP4rev1 SASL-IR LOGIN-REFERRALS ID ENABLE IDLE XLIST LITERAL+ STARTTLS LOGINDISABLED] Dovecot (Debian) ready.
              

              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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              • D
                daan
                last edited by daan

                Yes I know, when I do a packet capture on my WAN. I get an empty log
                76a90efe-9310-4c75-923f-340bcb2ecc44-image.png

                I know that the IMAP responds but I can't reach it with a E-Mail client

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                • johnpozJ
                  johnpoz LAYER 8 Global Moderator
                  last edited by johnpoz

                  Well then you not sniffing on the right interface, or the correct port?

                  Are you using PPPoE for your connection?

                  Or maybe there is something in front of your device answering for these ports? If what your saying is pfsense never sees the traffic. Then you have something in front of pfsense answering?

                  If your not seeing loads of traffic when you sniff on your wan... Then your sniffing on the wrong interface or you have something wrong with your packet capture.. Do a simple tcpdump from pfsense console.

                  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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                  • D
                    daan
                    last edited by daan

                    I used these settings
                    c32204af-dda3-4113-9070-dc960b91e94d-image.png

                    Pfsense is hooked up straight to my ISP modem, my LAN interface goes to a layer 2 cisco switch, the mail server is attached to the switch

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                    • johnpozJ
                      johnpoz LAYER 8 Global Moderator
                      last edited by johnpoz

                      Well do it without 143, do you see lots of traffic?

                      If you see lots of normal traffic, and nothing on 143 - then something in front of pfsense is answering for 143..

                      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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                      • D
                        daan
                        last edited by

                        When I do not specify a port I see loads of traffic, HTTPS traffic

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                        • johnpozJ
                          johnpoz LAYER 8 Global Moderator
                          last edited by johnpoz

                          Well then 143 is not getting to pfsense, but something answers on your IP (one connected to the forum with)

                          Maybe your ISP intercepts this traffic... But if pfsense never sees traffic to 143, how could it ever forward it?

                          This is why step one in any sort of this troubleshooting, is to actually VALIDATE traffic is getting to pfsense.. Pfsense can not do anything with something it never sees.

                          You sure pfsense wan is public address? Its not a rfc1918 address?

                          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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                          • V
                            viragomann @johnpoz
                            last edited by

                            @johnpoz said in Mail servers imap behind pfsense not reachable:

                            This is why step one in any sort of this troubleshooting, is to actually VALIDATE traffic is getting to pfsense.

                            Mentioned about eight times in this thread, but still seems to be ignored.

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                            • D
                              daan
                              last edited by

                              The mail server is on my current IP, but with my previous router it worked fine (Non pfsense).
                              And yes I am 1000% sure my pfsense WAN IP is my public IP, because all of my websites running from this network are up and reachable.

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                              • johnpozJ
                                johnpoz LAYER 8 Global Moderator
                                last edited by johnpoz

                                Well something is answering on his IP he is connecting to the forum with, which I would assume his IP... But from his packet capture - nothing is getting to pfsense..

                                Pfsense can not forward what it does not see.. This is basic 101 stuff here..

                                edit: I do not know what to tell you.. This is basic 101 stuff here, if you can not show us pfsense seeing the traffic on its wan... How could it ever do anything with it.. All I can tell you is something answers on 143 when I hit the IP you connected to the forum from..

                                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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                                • V
                                  viragomann @daan
                                  last edited by

                                  @daan said in Mail servers imap behind pfsense not reachable:

                                  When I do not specify a port I see loads of traffic, HTTPS traffic

                                  You can also limit the capture to multiple port by entering "143|587|993" for instance to take all IMAP ports.

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                                    viragomann @daan
                                    last edited by

                                    @daan
                                    You can check your real public IP on web services like https://whatismyipaddress.com

                                    The IP you get displayed there must match your pfSense WAN IP, otherwise there is a router in front of pfSense.

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                                    • D
                                      daan
                                      last edited by

                                      @viragomann I know my it is the same IP as the pfsense WAN interface IP

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                                      • D
                                        daan
                                        last edited by

                                        @johnpoz this is my capture with 143|465|587|993 as ports
                                        Screenshot 2020-09-25 1449523.png

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                                        • johnpozJ
                                          johnpoz LAYER 8 Global Moderator
                                          last edited by johnpoz

                                          Do a simple sniff on 143 then..

                                          Then go to can you see me . org and put in 143..

                                          You should see this traffic. Clearly sniffing is working.. But I don't see any traffic for 143.

                                          To be honest, sure looks to be working to me.. Whatever issues you might be having with imap has nothing to do with pfsense. I get a connection to 143, and sure seems to be whatever server your running behind pfsense.. reports Dovecot (Debian), which is what your Poste.io server uses for imap..

                                          btw I see 993 there in your sniff which would be imap over tls. Maybe your client is just not using 143 when you tested which is why you didn't see on sniff.. Do can you see me . org so you know exactly what port is being sent.

                                          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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                                          • V
                                            viragomann @daan
                                            last edited by viragomann

                                            @daan said in Mail servers imap behind pfsense not reachable:

                                            this is my capture with 143|465|587|993 as ports

                                            Ther is obviously a communiction on 993. Possibly your client switches automatically to 993 (SSL)?

                                            However, the traffic may be outbound as well. You're the only one who knows the destination IP, we cannot see it.

                                            GertjanG D 2 Replies Last reply Reply Quote 0
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