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    SMTP Out being blocked

    Scheduled Pinned Locked Moved Firewalling
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    • johnpozJ Offline
      johnpoz LAYER 8 Global Moderator @nabberuk
      last edited by

      @nabberuk said in SMTP Out being blocked:

      I can't find much on TCP:SEC

      SYN and the EC just means ECE, CWR were also set..

      See
      https://www.rfc-editor.org/rfc/rfc3168#section-23.2

      An intelligent man is sometimes forced to be drunk to spend time with his fools
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      • N Offline
        nabberuk @johnpoz
        last edited by nabberuk

        @johnpoz

        Packet capture with a filter for port 465. This looks normal.

        16:05:09.928638 IP [external_IP].9908 > 64.233.184.109.465: tcp 0
        16:05:12.942825 IP [external_IP].9908 > 64.233.184.109.465: tcp 0
        16:05:18.953456 IP [external_IP].9908 > 64.233.184.109.465: tcp 0
        16:05:28.633324 IP [external_IP].56949 > 64.233.184.109.465: tcp 0
        16:05:31.639172 IP [external_IP].56949 > 64.233.184.109.465: tcp 0
        16:05:37.647045 IP [external_IP].56949 > 64.233.184.109.465: tcp 0

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        • johnpozJ Offline
          johnpoz LAYER 8 Global Moderator @nabberuk
          last edited by

          @nabberuk yeah SEC is not anything odd.. Depend on what your application is setting.

          But you can clearly see traffic is leaving.. Just not getting any answers.. Which has nothing to do with pfsense.. Is your wan IP different? Maybe they don't want to talk to that IP, or maybe your isp is blocking.. But clearly from your sniff your sending that traffic out.. You getting an answer is out of pfsense control.

          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 25.07.1 | Lab VMs 2.8, 25.07.1

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          • N Offline
            nabberuk @johnpoz
            last edited by

            @johnpoz Thanks.

            I shall further investigate. I am using multiple WAN IP addresses but can't see any settings that would affect this.

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            • johnpozJ Offline
              johnpoz LAYER 8 Global Moderator @nabberuk
              last edited by

              @nabberuk I did a simple nmap from pfsense to that IP... And I show it answering on the 465 port.

              Running: /usr/local/bin/nmap  -sS -P0 -e igb1 '64.233.184.109'
              Starting Nmap 7.91 ( https://nmap.org ) at 2022-02-21 10:14 CST
              Nmap scan report for wa-in-f109.1e100.net (64.233.184.109)
              Host is up (0.11s latency).
              Not shown: 996 filtered ports
              PORT    STATE SERVICE
              465/tcp open  smtps
              587/tcp open  submission
              993/tcp open  imaps
              995/tcp open  pop3s
              
              Nmap done: 1 IP address (1 host up) scanned in 10.48 seconds
              
              

              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
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              • N Offline
                nabberuk @johnpoz
                last edited by nabberuk

                @johnpoz It works fine from my home connection, just not in our colocation dc. I have raised a query with them to see if they are blocking anything.

                Doing an nmap i get the following. Interestingly i can ping that IP from pfsense. Seems to be someone if blocking it upstream.

                Host discovery disabled (-Pn). All addresses will be marked 'up' and scan times will be slower.
                Starting Nmap 7.91 ( https://nmap.org ) at 2022-02-21 16:20 GMT
                setup_target: failed to determine route to 64.233.184.109
                WARNING: No targets were specified, so 0 hosts scanned.
                Nmap done: 0 IP addresses (0 hosts up) scanned in 0.03 seconds
                
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                • johnpozJ Offline
                  johnpoz LAYER 8 Global Moderator @nabberuk
                  last edited by

                  @nabberuk said in SMTP Out being blocked:

                  just not in our colocation dc

                  Yeah quite possible they don't let that sort of traffic out? Or could be gmail is blocking your IP because it sends just spam ;)

                  But your clearly sending it - so something upstream is blocking it, or its getting there and your just not getting back an answer.. All of which has nothing to do with pfsense.

                  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 25.07.1 | Lab VMs 2.8, 25.07.1

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                  • johnpozJ Offline
                    johnpoz LAYER 8 Global Moderator @nabberuk
                    last edited by

                    @nabberuk said in SMTP Out being blocked:

                    failed to determine route to 64.233.184.109

                    Where did you run that nmap?

                    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 25.07.1 | Lab VMs 2.8, 25.07.1

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                    • N Offline
                      nabberuk @johnpoz
                      last edited by nabberuk

                      @johnpoz from pfsense (diag > command prompt) after installing the package.

                      Now ran it from the nmap option. think its defiantly being blocked upstream.

                      Running: /usr/local/bin/nmap  -sS -P0 -e igb0 '64.233.184.109'
                      Starting Nmap 7.91 ( https://nmap.org ) at 2022-02-21 16:31 GMT
                      Nmap scan report for wa-in-f109.1e100.net (64.233.184.109)
                      Host is up (0.0096s latency).
                      Not shown: 998 filtered ports
                      PORT    STATE SERVICE
                      993/tcp open  imaps
                      995/tcp open  pop3s
                      
                      Nmap done: 1 IP address (1 host up) scanned in 6.53 seconds
                      
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                      • johnpozJ Offline
                        johnpoz LAYER 8 Global Moderator @nabberuk
                        last edited by johnpoz

                        @nabberuk did you pick your interface? I would think pfsense should of been able to figure out which interface to send the traffic.. but maybe you have something odd setup with your routing.

                        Was that sniff you saw going out your wan - you sure that is the correct "wan" to be able to get there?

                        edit: so you can see other open ports (get answers) but not 465 - interesting..

                        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 25.07.1 | Lab VMs 2.8, 25.07.1

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