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    Mail server behind pfSense

    Scheduled Pinned Locked Moved Firewalling
    7 Posts 4 Posters 1.6k Views
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    • S
      skeating
      last edited by

      Hello

      I am using a pfSense firewall in front of an Ability Mail Server. The firewall does NAT for the mail server. when I use MXToolbox to SMTP test the mail server, there are two results:

      SMTP Valid Hostname      Reverse DNS is not a valid Hostname

      SMTP Banner check          Revers DNS does not match SMTP Banner

      I have had a problem in the past where the pfSense firewall IP shows up on block lists, not the mail server IP. I know that since the firewall is in front, that is what any receiving server will 'see' the mail to be coming from. My question is, is there a setting or a rule that needs to be added, so that a reverse DNS lookup will go through to the mail server.

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      • V
        viragomann
        last edited by

        The reverse DNS entry has to be set on a public DNS.

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        • chpalmerC
          chpalmer
          last edited by

          After you fix your rdns the SMTP Banner is set in the mail server to match it.

          ???

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

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          • S
            skeating
            last edited by

            I checked our DNS, and there are correct PTR records for the domain name. Interestingly, when I use MXToolbox's REverse DNS lookup, the PTR records are there.

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            • V
              viragomann
              last edited by

              The MXToolBox result says that the hostname is not valid.
              Hard to give a better support as long we don't know the real hostname.

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              • johnpozJ
                johnpoz LAYER 8 Global Moderator
                last edited by

                Happy to take a look - but as viragomann correctly states without knowing the domain your taking about its hard to help.. You could PM me the domain and I will check its mx record and the the PTR, and what the banner shows when connecting to the MX, etc.

                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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                • johnpozJ
                  johnpoz LAYER 8 Global Moderator
                  last edited by

                  So I got your email.. I replied.  Your PTR returns multiple multiple entries..  1 of which is yours out of the 10 that come back.

                  And your banner does not match.. your PTR is mail1.yourdomain.tld while your banner is just some other domain.tld

                  So yeah your going to have problems!

                  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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