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    Mail servers imap behind pfsense not reachable

    Scheduled Pinned Locked Moved Firewalling
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    • GertjanG
      Gertjan
      last edited by

      1e7b2090-74e1-4446-8e3b-ca3df2f86c2b-image.png

      STARTTLS seems strange when using 993 as there can't be a TLS negotiation - it will be a direct SSL/TLS connection, like your 465 = SMTPS outgoing mail connection.

      No "help me" PM's please. Use the forum, the community will thank you.
      Edit : and where are the logs ??

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      • D
        daan @johnpoz
        last edited by

        @johnpoz Same story when I use port 143, it does not connect.
        Yes I know what pfsense does, but why did it work fine on my previous router and not on my pfsense router?

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          daan @Gertjan
          last edited by

          @Gertjan My mail server does TLS over port 993
          df9c81dd-cd73-48c9-928b-5ae0cd9c6053-image.png
          (POP, HTTP and HTTPS are not forwarded)

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          • johnpozJ
            johnpoz LAYER 8 Global Moderator
            last edited by

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

            Same story when I use port 143, it does not connect.

            It does connect.. I have connected via 143..

            connect.png

            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
              last edited by

              Since we cannot see any unencryted connection attempts, I think it's a legitimate question, if there is a valid SSL certificate installed on the IMAP server.

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                daan @johnpoz
                last edited by

                @johnpoz Wattt the hell, when I do the same it returns
                29d7ebdc-0255-441d-a993-44ac60e67925-image.png

                bmeeksB 1 Reply Last reply Reply Quote 0
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                  daan @viragomann
                  last edited by

                  @viragomann Yes there is, I am using Let's encrypt mail certificates.

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                    viragomann @daan
                    last edited by

                    @daan
                    Let's Encrypt is no surety for validation. Possibly the update job failed.

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                    • bmeeksB
                      bmeeks @daan
                      last edited by bmeeks

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

                      @johnpoz Wattt the hell, when I do the same it returns
                      29d7ebdc-0255-441d-a993-44ac60e67925-image.png

                      Is your client trying to connect from inside your LAN or outside? This could be a NAT reflection issue. Unless you have split DNS set up so that internal clients get routed straight to the mail server's internal IP and not out the WAN, then they can't connect unless you configure that ugly beast, NAT reflection.

                      That might be why @johnpoz can connect, but you can't. He is outside of your LAN. The standard port forward setup is going to port forward only traffic coming from the Internet into your WAN connection. It won't port forward traffic coming from your LAN side. Your previous router may have automatically configured NAT reflection when you configured a port forward. pfSense does not automatically configure NAT reflection for you.

                      Your screenshot of the email client shows that you have configured the mail server with its hostname of "mail.xxxx.xxx", so your client will ask DNS for the corresponding IP. Since I'm betting you have your MX record in DNS pointing to your WAN IP, then your internal client will try to connect to the IMAP server using your WAN's external public IP. That's where the NAT reflection would come in. Without it, that traffic does not find your internal mail host. To see if I am correct, instead of the mail server's hostname, put it's actual internal IP address in the mail client's setup and see if it works then.

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                      • johnpozJ
                        johnpoz LAYER 8 Global Moderator
                        last edited by johnpoz

                        ^exactly.

                        To be honest this comes up pretty much every single day.. Which is why I suggested can you see me . org... You have to validate traffic is getting to you from the public internet.

                        If your setting on some box on your local network, and hitting your wan IP.. Its only going to work if you have nat reflection setup, and that is actually working. depending on the protocol, and how you set it up, or where your client is exactly compared to you, same vlan or different..

                        And its just plain an abominations to all things holy about networking in the first place.

                        Maybe your setup worked how you were testing it before with your old router because it was doing nat reflection. Which pfsense doesn't do without you actually setting it up.

                        If was up to me - the whole nat reflection nonsense wouldn't even be an option.. Because its a hack, always has been a hack.. And really should never be used on any sort of real network.. Its fine for billy the user and his soho router that doesn't understand dns, doesn't really understand IPs anyway... And think he should just be able to put in his ddns address into his browser and hit xyz that is running on his own freaking box, or the raspberry pie he clicked go on for some service.

                        But if your to the point where your running something like pfsense, and working with email servers and the like.. Time to leave the hacky lets make it work for billy bob the user because he doesn't know how to actually setup a real network anyway toys away.

                        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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                          daan @bmeeks
                          last edited by

                          @bmeeks Thanks for the explanation, When I use my IP as IMAP and SMTP it can't connect either.

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                          • johnpozJ
                            johnpoz LAYER 8 Global Moderator
                            last edited by johnpoz

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

                            When I use my IP as IMAP and SMTP it can't connect either.

                            What IP?? Again you need to be OUTSIDE YOUR NETWORK!! If your going to do it from inside, you need to setup nat reflection. Or just use your internal IP.

                            I can connect to your IP just fine from outside..

                            Just tested again, and pops right in...

                            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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                              daan
                              last edited by

                              Yes I understand, chill bro. I got it working I did not know that I had to setup NAT reflection, like I said earlier I am new to pfsense.
                              Thanks for the help and detailed explanations, have a good day!

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                              • johnpozJ
                                johnpoz LAYER 8 Global Moderator
                                last edited by

                                Then what was the point of this

                                When I use my IP as IMAP and SMTP it can't connect either.

                                If you have it working?

                                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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                                  PhxAzCraig @daan
                                  last edited by

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

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

                                  It looks to me like you are closer than you think - you're simply using all encrypted ports. I see traffic on port 993, which is imap over SSL. I also see port 465, which is SMTP over SSL.

                                  Furthermore, the traffic is actually flowing in both directions. You can see port 993 going from left to right in the first line, and you can see the reply coming back on the second line. The conversation is taking place with ports 993 and 7256. (Original connection on port 993 with reply requested on 7256). Later down you see the same thing happening with port 465.

                                  It looks like everything is working. I'm wondering why you don't see IMAP mail in your mail client, because the connection is there.

                                  Incidentally, the way I would test something like this is to put a laptop directly on the WAN side of the firewall - you can use it in place of your cable modem and use the same IP address on the laptop as the gateway. Or plug it in in parallel with the internet but give yourself a public IP in the same subnet as the WAN IP address. Then test to the pfSense IP while running wireshark to see if your mail client is even sending port 143.

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                                    daan @johnpoz
                                    last edited by

                                    @johnpoz To answer @bmeeks question

                                    bmeeksB 1 Reply Last reply Reply Quote 0
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                                      daan @PhxAzCraig
                                      last edited by

                                      @PhxAzCraig It is working now I had to setup NAT reflection, Thanks!

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                                      • Bob.DigB
                                        Bob.Dig LAYER 8
                                        last edited by

                                        @johnpoz In my home setup, I can "test port" my own email server on my public IP. I also can connect my xmpp Client to my XMPP Server. I have not setup any NAT Reflection in my pfsense or rules.

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                                        • bmeeksB
                                          bmeeks @daan
                                          last edited by

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

                                          @johnpoz To answer @bmeeks question

                                          @daan, when we say from "inside the LAN" we meant put in the actual internal RFC1918 address of your mail server. So maybe something like 192.168.1.xxx or whatever -- NOT your DNS entry IP (in other words, not the public IP). If using the actual internal non-NAT IP of the mail server didn't work, then a firewall rule must have been blocking. Is that mail server on a separate interface perhaps such as some kind of DMZ?

                                          Glad you got it working with NAT reflection, but the preferred way of doing this is with a split-DNS arrangement such that clients on your LAN connect directly to the mail server using it's local non-NAT IP address. For users out on the Internet, they would get the WAN public IP when asking for the mail server. You can research split-DNS to see how this works and why it is the preferred solution over NAT reflection.

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                                            daan
                                            last edited by

                                            @bmeeks Ah okay, I'll take a look at that. Thanks for the tip!

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