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    Postfix forwarder - modify SMTP banner?

    Scheduled Pinned Locked Moved pfSense Packages
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    • D
      doktornotor Banned
      last edited by

      Afraid the postfix package is broken - gethostname() not working. Otherwise, you'd get "pfsense.domain.com" in the smtpd_banner. You can try to add

      
      myhostname = host.domain.com
      
      

      to custom configuration and see if it helps.

      1 Reply Last reply Reply Quote 0
      • D
        dreadnought
        last edited by

        @doktornotor:

        Afraid the postfix package is broken - gethostname() not working. Otherwise, you'd get "pfsense.domain.com" in the smtpd_banner. You can try to add

        
        myhostname = host.domain.com
        
        

        to custom configuration and see if it helps.

        Is it possible the RBL lookups are broken as well?  I think postfix forwarder is reducing the volume of spam (though this is just anecdotal, I don't see any useful logs in the GUI), but the first spam I received this morning came from an IP address that should have been blocked by the postfix forwarder RBL lookup.

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        • D
          doktornotor Banned
          last edited by

          Well, if basic things like resolution of local hostname are broken, then obviously yes, DNSBLs which rely on DNS records may be broken as well. Would need the whole postconf output (without -n) to see what's really configured in the end.

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          • M
            mschiek01
            last edited by

            @dreadnought:

            @doktornotor:

            Afraid the postfix package is broken - gethostname() not working. Otherwise, you'd get "pfsense.domain.com" in the smtpd_banner. You can try to add

            
            myhostname = host.domain.com
            
            

            to custom configuration and see if it helps.

            Is it possible the RBL lookups are broken as well?  I think postfix forwarder is reducing the volume of spam (though this is just anecdotal, I don't see any useful logs in the GUI), but the first spam I received this morning came from an IP address that should have been blocked by the postfix forwarder RBL lookup.

            I have been running it for months on multiple boxes. As far as I know nothing is broken as long as it intstalled correctly.

            First you NEED to look at the log.

            1. Do this, go into the first page general configuration, second heading "Logging"  it should say "/var/log/maillog"  if not use the down arrow and select it and save the configuration.

            2. Go into services and restart postfix.

            3. you can do this anyway you want.  You said you tried to use edit file which is fine, use it browse to var/log/maillog and open it what does it say?  Post the log here

            Again I do not think postfix is actually receiving your mail.  It needs to be in the middle between pfsense and your smtp server.  If you see it running in services then it probably is.

            Were you running an smtp server without it before? If so did you modify your firewall route to pass the mail to postfix first.  Just installing it will not do this.

            This is very easy to test.  
            1. Stop your SMTP server NOT postfix.
            2. Run a test with mxtoolbox
            3. Do you get a responce
            3a No -> postfix is not in the middle and IS not processing mail for you.
            3b Yes -> postfix is in the middle.

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            • D
              dreadnought
              last edited by

              I have been running it for months on multiple boxes. As far as I know nothing is broken as long as it intstalled correctly.

              First you NEED to look at the log.

              1. Do this, go into the first page general configuration, second heading "Logging"  it should say "/var/log/maillog"  if not use the down arrow and select it and save the configuration.

              2. Go into services and restart postfix.

              3. you can do this anyway you want.  You said you tried to use edit file which is fine, use it browse to var/log/maillog and open it what does it say?  Post the log here

              Again I do not think postfix is actually receiving your mail.  It needs to be in the middle between pfsense and your smtp server.  If you see it running in services then it probably is.

              Were you running an smtp server without it before? If so did you modify your firewall route to pass the mail to postfix first.  Just installing it will not do this.

              This is very easy to test.  
              1. Stop your SMTP server NOT postfix.
              2. Run a test with mxtoolbox
              3. Do you get a responce
              3a No -> postfix is not in the middle and IS not processing mail for you.
              3b Yes -> postfix is in the middle.

              Ok, logging was set for "System log" - I changed it to "/var/log/maillog".

              I don't see a way to restart Postfix, so I went into Services/Postfix Forwarder, unchecked "Enable Postfix" then saved and then rechecked it then saved.

              From the command prompt on the Netgate firewall I tried "cat /var/log/maillog" but nothing happened.

              If I go to "System Activity" I see:

              42792 postfix    64   20 87216K 50644K nanslp  2   0:02  0.00% perl5.12.4
              32099 postfix    64   20 87216K 50520K nanslp  1   0:02  0.00% perl5.12.4
              51351 postfix    64   20 87216K 50644K nanslp  1   0:02  0.00% perl5.12.4
              59513 postfix    64   20 87216K 50644K nanslp  2   0:02  0.00% perl5.12.4
              2313 postfix    64   20 87216K 50644K nanslp  2   0:02  0.00% perl5.12.4

              Regarding the firewall rule… there is a postfix forwarder option for "Domains to Forward" and I put my mail server's IP in there along with the domains.  If this didn't create a firewall rule, then it sounds like that's where I screwed up and I may have misinterpreted the mxtoolbox results.

              Actually, I'm still getting email from my mail server... so that doesn't make sense.  I'll go back and read your posts again.

              Edit: Now I see none of my NAT or firewall rules related to SMTP were updated by the installation of postfix forwarder.  Combination of misinterpreting mxtoolbox output and a slow spam night doomed me while I was troubleshooting.  Fixing the rules now.  Thanks for the help!

              1 Reply Last reply Reply Quote 0
              • M
                mschiek01
                last edited by

                @dreadnought:

                I have been running it for months on multiple boxes. As far as I know nothing is broken as long as it intstalled correctly.

                First you NEED to look at the log.

                1. Do this, go into the first page general configuration, second heading "Logging"  it should say "/var/log/maillog"  if not use the down arrow and select it and save the configuration.

                2. Go into services and restart postfix.

                3. you can do this anyway you want.  You said you tried to use edit file which is fine, use it browse to var/log/maillog and open it what does it say?  Post the log here

                Again I do not think postfix is actually receiving your mail.  It needs to be in the middle between pfsense and your smtp server.  If you see it running in services then it probably is.

                Were you running an smtp server without it before? If so did you modify your firewall route to pass the mail to postfix first.  Just installing it will not do this.

                This is very easy to test.  
                1. Stop your SMTP server NOT postfix.
                2. Run a test with mxtoolbox
                3. Do you get a responce
                3a No -> postfix is not in the middle and IS not processing mail for you.
                3b Yes -> postfix is in the middle.

                Ok, logging was set for "System log" - I changed it to "/var/log/maillog".

                I don't see a way to restart Postfix, so I went into Services/Postfix Forwarder, unchecked "Enable Postfix" then saved and then rechecked it then saved.

                From the command prompt on the Netgate firewall I tried "cat /var/log/maillog" but nothing happened.

                If I go to "System Activity" I see:

                42792 postfix    64   20 87216K 50644K nanslp  2   0:02  0.00% perl5.12.4
                32099 postfix    64   20 87216K 50520K nanslp  1   0:02  0.00% perl5.12.4
                51351 postfix    64   20 87216K 50644K nanslp  1   0:02  0.00% perl5.12.4
                59513 postfix    64   20 87216K 50644K nanslp  2   0:02  0.00% perl5.12.4
                2313 postfix    64   20 87216K 50644K nanslp  2   0:02  0.00% perl5.12.4

                Regarding the firewall rule… there is a postfix forwarder option for "Domains to Forward" and I put my mail server's IP in there along with the domains.  If this didn't create a firewall rule, then it sounds like that's where I screwed up and I may have misinterpreted the mxtoolbox results.

                Actually, I'm still getting email from my mail server... so that doesn't make sense.  I'll go back and read your posts again.

                With postfix running just stop your mail server and run the test with mxtoolbox.  If you receive a reply it is configured correctly if you do not receive a reply it is not.  Let me know the results.

                1 Reply Last reply Reply Quote 0
                • D
                  dreadnought
                  last edited by

                  With postfix running just stop your mail server and run the test with mxtoolbox.  If you receive a reply it is configured correctly if you do not receive a reply it is not.  Let me know the results.

                  With my mail server shut down, I got a timeout from mxtoolbox.  The firewall rule I used on the WAN interface after I re-read your posts was:

                  TCP * * 127.0.0.1 25 (SMTP) * none

                  And I changed Listen interface(s) in postfix forwarder to loopback.

                  I must be doing something wrong with the firewall rules because it appears postfix forwarder IS running, just not answering.

                  I have tried having the rule above enabled both with my previous rule for my internal server enabled and disabled, but either way postfix forwarder doesn't answer on port 25.

                  Update:

                  I've been reading through http://forum.pfsense.org/index.php/topic,40622.msg217539.html#msg217539, particularly:

                  "remove nat from port 25
                  create a wan rule to permit smtp traffic to wan address
                  check enable postfix option
                  choose at least wan loopback interfaces
                  fill your domain/internal smtp info"

                  I follow this except for the "at least" part… maybe I need to try using the WAN interface instead of loopback.

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                  • M
                    mschiek01
                    last edited by

                    @dreadnought:

                    With postfix running just stop your mail server and run the test with mxtoolbox.  If you receive a reply it is configured correctly if you do not receive a reply it is not.  Let me know the results.

                    With my mail server shut down, I got a timeout from mxtoolbox.  The firewall rule I used on the WAN interface after I re-read your posts was:

                    TCP * * 127.0.0.1 25 (SMTP) * none

                    And I changed Listen interface(s) in postfix forwarder to loopback.

                    I must be doing something wrong with the firewall rules because it appears postfix forwarder IS running, just not answering.

                    I have tried having the rule above enabled both with my previous rule for my internal server enabled and disabled, but either way postfix forwarder doesn't answer on port 25.

                    Update:

                    I've been reading through http://forum.pfsense.org/index.php/topic,40622.msg217539.html#msg217539, particularly:

                    "remove nat from port 25
                    create a wan rule to permit smtp traffic to wan address
                    check enable postfix option
                    choose at least wan loopback interfaces
                    fill your domain/internal smtp info"

                    I follow this except for the "at least" part… maybe I need to try using the WAN interface instead of loopback.

                    You can do it as above.  However do not use the rule I gave you.  Instead use the rule above and change the listening interface to the wan and loopback.  Just use the control key to select both.  Then save the configuration.  Then rerun the mxtoolbox test with your smtp server stopped but postfix enabled and running.  you should get a responce.

                    1 Reply Last reply Reply Quote 0
                    • D
                      dreadnought
                      last edited by

                      I follow this except for the "at least" part… maybe I need to try using the WAN interface instead of loopback.

                      That seems to have worked… I changed the rule to:

                      TCP * * WAN address 25 (SMTP) * none

                      And now postfix forwarder is answering... and emails are getting to my internal mail server.

                      1 Reply Last reply Reply Quote 0
                      • M
                        mschiek01
                        last edited by

                        Good.  :)

                        You still should go to /var/log/maillog

                        And take a look and see what postfix is doing and see if there are any other problems.

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                        • M
                          mschiek01
                          last edited by

                          @dreadnought:

                          I follow this except for the "at least" part… maybe I need to try using the WAN interface instead of loopback.

                          That seems to have worked… I changed the rule to:

                          TCP * * WAN address 25 (SMTP) * none

                          And now postfix forwarder is answering... and emails are getting to my internal mail server.

                          It should be answering now with whatever you put in smtpd_banner = $myhostname

                          1 Reply Last reply Reply Quote 0
                          • D
                            dreadnought
                            last edited by

                            @mschiek01:

                            Good.  :)

                            You still should go to /var/log/maillog

                            And take a look and see what postfix is doing and see if there are any other problems.

                            I thought I replied to this but don't see it… anyway, I changed the postfix forwarder logging option to /var/log/maillog.  This file is 0 bytes when I download it from the pfsense GUI.  The Postfix dashboard widget is also just a blue bar that says Postfix.  This was the case before and after my changing the logging from System logs to /var/log/maillog.  Confused!  It appears email is being processed fine as I'm receiving it from my internal mail server and the headers mention my pfsense.domain.com.

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                            • M
                              mschiek01
                              last edited by

                              Try rebooting the box.  Then take a look at the log and see if it is logging properly.

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                              • D
                                dreadnought
                                last edited by

                                @mschiek01:

                                Try rebooting the box.  Then take a look at the log and see if it is logging properly.

                                When all else fails… yeah, that worked.  After rebooting I can now download and view /var/log/maillog and there are stats in the Postfix dashboard widget.

                                It will be nice not having any more spam from Dr. Oz.  Not that you guys would know about that, because you've been blocking his mail.  And now I am too.  ;)

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                                • M
                                  mschiek01
                                  last edited by

                                  @dreadnought:

                                  @mschiek01:

                                  Good.  :)

                                  You still should go to /var/log/maillog

                                  And take a look and see what postfix is doing and see if there are any other problems.

                                  I thought I replied to this but don't see it… anyway, I changed the postfix forwarder logging option to /var/log/maillog.  This file is 0 bytes when I download it from the pfsense GUI.  The Postfix dashboard widget is also just a blue bar that says Postfix.  This was the case before and after my changing the logging from System logs to /var/log/maillog.  Confused!  It appears email is being processed fine as I'm receiving it from my internal mail server and the headers mention my pfsense.domain.com.

                                  Also did you configure the tabs in postfix  "access lists" and "antispam"

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                                  • D
                                    dreadnought
                                    last edited by

                                    Also did you configure the tabs in postfix  "access lists" and "antispam"

                                    Antispam yes… access lists no.  In terms of the "Client Access List", I force users to connect to the LAN via VPN to send mail.  So I don't think I need to let postfix forwarder know about clients allowed to relay, because no one is?

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                                    • D
                                      dreadnought
                                      last edited by

                                      Any idea where the Postfix dashboard widget gets its data?  It currently shows:

                                      Postfix
                                      2013-08-16
                                      Sent
                                      2

                                      But I can see from /var/log/maillog (and from my inbox) that a lot more stuff has happened… e.g. rejections.

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                                      • M
                                        mschiek01
                                        last edited by

                                        @dreadnought:

                                        Also did you configure the tabs in postfix  "access lists" and "antispam"

                                        Antispam yes… access lists no.  In terms of the "Client Access List", I force users to connect to the LAN via VPN to send mail.  So I don't think I need to let postfix forwarder know about clients allowed to relay, because no one is?

                                        You are thinking the wrong direction.  the ACL is what postfix uses to process the email.  The key word being accept as in "INBOUND" mail.  Not outbound as it does not have any thing to do with outbound mail.

                                        What you are seeing in the dashboard is correct.  The Sent actually refers to received.  So it received 2 emails from x and forwarded it to you smtp server.

                                        Are you using mailscanner?

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                                        • D
                                          dreadnought
                                          last edited by

                                          @mschiek01:

                                          @dreadnought:

                                          Also did you configure the tabs in postfix  "access lists" and "antispam"

                                          Antispam yes… access lists no.  In terms of the "Client Access List", I force users to connect to the LAN via VPN to send mail.  So I don't think I need to let postfix forwarder know about clients allowed to relay, because no one is?

                                          You are thinking the wrong direction.  the ACL is what postfix uses to process the email.  The key word being accept as in "INBOUND" mail.  Not outbound as it does not have any thing to do with outbound mail.

                                          What you are seeing in the dashboard is correct.  The Sent actually refers to received.  So it received 2 emails from x and forwarded it to you smtp server.

                                          Are you using mailscanner?

                                          Oh… I think I get it now.  So the ACL is to whitelist my computers in case they send spammy-looking email, they won't be blocked by postfix forwarder?  I think I'll leave the entire set of options in that tab empty for now.

                                          I thought the dashboard would show rejections, but it looks like it does not... I just have #s for sent and bounced, but I know many more messages are being rejected from looking at /var/log/maillog.

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                                          • M
                                            mschiek01
                                            last edited by

                                            you are correct.

                                            1 Reply Last reply Reply Quote 0
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