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Re: Is a late header check possible?

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  • Noel Jones
    ... I ll assume your content_filter reinjects mail to localhost:10025 after processing. Note: make sure your post-filter header checks don t ever reject mail.
    Message 1 of 28 , Feb 7, 2013
      On 2/7/2013 8:58 AM, Titanus Eramius wrote:
      > I'm running SpamAssassin as a content_filter on incoming mail which ads
      > 4 spam-headers, one of them being "X-Spam-Level:". The precise
      > header varies, depending on the spamscore. SpamAssassin ads one "*" for
      > each spampoint, so a example-header could be:
      >
      > X-Spam-Level: ********************
      >
      > I would like to have the ability to redirect mails with that header to
      > a account where I can store them.
      >
      > So basically I *think* I'm asking if Postfix have a header_checks
      > feature that runs after the content filters?

      I'll assume your content_filter reinjects mail to localhost:10025
      after processing.

      Note: make sure your post-filter header checks don't ever reject
      mail. That would make you a backscatter source and get you blacklisted.

      The cleanest way to do this is a separate postfix instance (not just
      a master.cf listener service) that listens on 10025, with its own
      header_checks. This also gives the very nice benefit of separation
      between pre-filter and post-filter mail.
      http://www.postfix.org/MULTI_INSTANCE_README.html



      Alternately, you can do some master.cf gyrations. This is likely
      easier to set up, but more confusing long-term. Something like:

      # master.cf
      # existing reinjection listener
      127.0.0.1:10025 inet n - n - - smtpd
      ... existing stuff ...
      -o cleanup_service_name=cleanup_filter

      # copy of the existing cleanup service
      cleanup_filter unix n - n - 0 cleanup
      -o header_checks=pcre:/etc/postfix/header_checks_filter
      -o body_checks=

      and then put your after-filter checks in header_checks_filter.




      -- Noel Jones
    • Titanus Eramius
      Thu, 07 Feb 2013 10:03:32 -0600 skrev Noel Jones ... Thank you for the reply Noel, it s very helpful as usual. The multi instance seems like the best solution,
      Message 2 of 28 , Feb 8, 2013
        Thu, 07 Feb 2013 10:03:32 -0600 skrev Noel Jones
        <njones@...>:

        > On 2/7/2013 8:58 AM, Titanus Eramius wrote:
        > > I'm running SpamAssassin as a content_filter on incoming mail which
        > > ads 4 spam-headers, one of them being "X-Spam-Level:". The precise
        > > header varies, depending on the spamscore. SpamAssassin ads one "*"
        > > for each spampoint, so a example-header could be:
        > >
        > > X-Spam-Level: ********************
        > >
        > > I would like to have the ability to redirect mails with that header
        > > to a account where I can store them.
        > >
        > > So basically I *think* I'm asking if Postfix have a header_checks
        > > feature that runs after the content filters?
        >
        > I'll assume your content_filter reinjects mail to localhost:10025
        > after processing.
        >
        > Note: make sure your post-filter header checks don't ever reject
        > mail. That would make you a backscatter source and get you
        > blacklisted.
        >
        > The cleanest way to do this is a separate postfix instance (not just
        > a master.cf listener service) that listens on 10025, with its own
        > header_checks. This also gives the very nice benefit of separation
        > between pre-filter and post-filter mail.
        > http://www.postfix.org/MULTI_INSTANCE_README.html

        Thank you for the reply Noel, it's very helpful as usual.

        The multi instance seems like the best solution, so I'll most likely go
        with that.
        And thanks for the warning.
      • Titanus Eramius
        Hi all Please note that the last time I asked about the behavior of Postfix it turned out I had misunderstood the concept of relaying mail. It might be the
        Message 3 of 28 , Feb 8, 2013
          Hi all

          Please note that the last time I asked about the behavior of Postfix it
          turned out I had misunderstood the concept of relaying mail. It might
          be the case again.

          I'm running the mailserver that serves this domain + a few others,
          the mailserver at ubuntudanmark.dk and the mailservers at nt-data.dk.

          So I'm running these servers, with this relation:
          mx01.aptget.dk <-- Not a backup MX
          mx01.ubuntudanmark.dk <-- Not a backup MX
          mx01.nt-data.dk <-- Backup MX for mx01.aptget.dk and
          mx01.ubuntudanmark.dk
          mx02.nt-data.dk <-- Backup MX for mx01.nt-data.dk

          The setup is entirely virtual, using MySQL to store aliases, addressees
          etc. The problem is, that *I think* the backup MX' can be used to
          spread backscatter. I routinely looks at the Postfix logging, and found
          these entries yesterday from mx01.nt-data.dk:

          ---
          titanus@ntdata:/var/log$ grep "048341743609" mail.log.1

          Feb 7 22:12:48 ntdata postfix/pickup[24843]: 048341743609: uid=5005
          from=<SRS0=3u76=L7=gmail.com=jimmiedcu949@...>

          Feb 7 22:12:48 ntdata postfix/cleanup[30176]: 048341743609:
          message-id=<GI63Z8-USKQ93-NH@...>

          Feb 7 22:12:48 ntdata postfix/qmgr[20252]: 048341743609:
          from=<SRS0=3u76=L7=gmail.com=jimmiedcu949@...>, size=5268,
          nrcpt=1 (queue active)

          Feb 7 22:12:48 ntdata postfix/smtp[30181]: 048341743609:
          to=<acer@...>,
          relay=mx01.ubuntudanmark.dk[31.192.231.5]:25, delay=0.71,
          delays=0/0.04/0.17/0.5, dsn=5.1.1, status=bounced (host
          mx01.ubuntudanmark.dk[31.192.231.5] said: 550 5.1.1
          <acer@...>: Recipient address rejected: User unknown in
          virtual mailbox table (in reply to RCPT TO command))

          Feb 7 22:12:48 ntdata postfix/bounce[30182]: 048341743609: sender
          non-delivery notification: B201D1743608

          Feb 7 22:12:48 ntdata postfix/qmgr[20252]: 048341743609: removed
          ---

          Then mx01.nt-data.dk tries to send a bounce to gmail:

          ---
          Feb 7 22:12:52 ntdata postfix/smtp[30183]: B201D1743608:
          to=<jimmiedcu949@...>,
          orig_to=<SRS0=3u76=L7=gmail.com=jimmiedcu949@...>,
          relay=gmail-smtp-in.l.google.com[173.194.71.26]:25, delay=3.4,
          delays=0.01/0.01/0.29/3, dsn=5.1.1, status=bounced (host
          gmail-smtp-in.l.google.com[173.194.71.26] said: 550-5.1.1 The email
          account that you tried to reach does not exist. Please try 550-5.1.1
          double-checking the recipient's email address for typos or 550-5.1.1
          unnecessary spaces. Learn more at 550 5.1.1
          http://support.google.com/mail/bin/answer.py?answer=6596
          bc7si9536557lbb.184 - gsmtp (in reply to RCPT TO command))
          ---

          The address acer@... does not exist - Neither at
          mx01.nt-data.dk nor at mx01.ubuntudanmark.dk, so I would like
          mx01.nt-data.dk to reject messages to it. I've tried with other
          non-existent addresses trough telnet, and mx01.nt-data.dk accepts them,
          as long as they are to one of the backup domains, and then bounces them
          (so currently they are disabled in the database).

          Following is postconf -n, the content of the 2 relay_* MySQL-files, and
          the structure of their database. If more is needed, then please let me
          know and I'll include it.

          Any pointers, examples or explanations will be appreciated. I've read
          in the documentation for virtual hosting and backup MX', but the answer
          seems to evades me.

          Thanks


          ntdata:/etc/postfix# postconf -n

          alias_maps = hash:/etc/aliases

          bounce_template_file = /etc/postfix/bounce.cf

          broken_sasl_auth_clients = yes

          config_directory = /etc/postfix

          delay_warning_time = 4

          disable_vrfy_command = yes

          inet_interfaces = all

          maximal_queue_lifetime = 15

          myhostname = ntdata.nt-data.dk

          mynetworks = 127.0.0.0/8

          recipient_canonical_classes = envelope_recipient

          recipient_canonical_maps = hash:/etc/postfix/pfix-no-srs.cf,
          tcp:127.0.0.1:10002

          relay_domains = proxy:mysql:/etc/postfix/relay_domains.cf

          relay_recipient_maps = proxy:mysql:/etc/postfix/relay_recipient_maps.cf

          sender_canonical_classes = envelope_sender

          sender_canonical_maps = hash:/etc/postfix/pfix-no-srs.cf,
          tcp:127.0.0.1:10001

          smtp_tls_security_level = may

          smtp_tls_session_cache_database =
          btree:$data_directory/smtp_tls_session_cache

          smtpd_data_restrictions =
          reject_unauth_pipelining,
          reject_multi_recipient_bounce,
          permit

          smtpd_helo_required = yes

          smtpd_recipient_restrictions =
          reject_non_fqdn_sender,
          reject_non_fqdn_recipient,
          reject_unknown_sender_domain,
          reject_unknown_recipient_domain,
          reject_rbl_client truncate.gbudb.net,
          reject_unauth_destination,
          permit

          smtpd_sasl_auth_enable = yes

          smtpd_sasl_exceptions_networks = $mynetworks

          smtpd_sasl_path = private/auth

          smtpd_sasl_security_options = noanonymous

          smtpd_sasl_type = dovecot

          smtpd_tls_ask_ccert = yes

          smtpd_tls_cert_file = /etc/ssl/self-signed/smtpd.crt

          smtpd_tls_key_file = /etc/ssl/self-signed/smtpd.key

          smtpd_tls_loglevel = 1

          smtpd_tls_received_header = yes

          smtpd_tls_security_level = may

          smtpd_tls_session_cache_database =
          btree:$data_directory/smtpd_tls_session_cache

          tls_random_source = dev:/dev/urandom

          transport_maps = hash:/etc/postfix/transport.cf

          virtual_alias_maps = proxy:mysql:/etc/postfix/virtual_alias_maps.cf

          virtual_gid_maps = static:5000

          virtual_mailbox_base = /home/vmail

          virtual_mailbox_domains =
          proxy:mysql:/etc/postfix/virtual_domains_maps.cf

          virtual_mailbox_maps = proxy:mysql:/etc/postfix/virtual_mailbox_maps.cf

          virtual_minimum_uid = 5000

          virtual_transport = dovecot

          virtual_uid_maps = static:5000


          ntdata:/etc/postfix# cat relay_domains.cf
          user = postfix
          password =
          dbname = postfix
          query = SELECT description FROM domain WHERE domain='%s' AND
          backupmx='1' AND active='1';

          ntdata:/etc/postfix# cat relay_recipient_maps.cf
          user = postfix
          password =
          dbname = postfix
          query = SELECT goto FROM alias WHERE address='%s' AND active='1';


          mysql> use postfix;
          mysql> desc domain;
          +-------------+--------------+------+-----+---------------------+------
          | Field | Type | Null | Key | Default | Extra
          +-------------+--------------+------+-----+---------------------+------
          | domain | varchar(255) | NO | PRI | NULL |
          | description | varchar(255) | NO | | NULL |
          | aliases | int(10) | NO | | 0 |
          | mailboxes | int(10) | NO | | 0 |
          | maxquota | bigint(20) | NO | | 0 |
          | quota | bigint(20) | NO | | 0 |
          | transport | varchar(255) | NO | | NULL |
          | backupmx | tinyint(1) | NO | | 0 |
          | created | datetime | NO | | 0000-00-00 00:00:00 |
          | modified | datetime | NO | | 0000-00-00 00:00:00 |
          | active | tinyint(1) | NO | | 1 |
          +-------------+--------------+------+-----+---------------------+------

          mysql> desc alias;
          +----------+--------------+------+-----+---------------------+-------+
          | Field | Type | Null | Key | Default | Extra |
          +----------+--------------+------+-----+---------------------+-------+
          | address | varchar(255) | NO | PRI | NULL | |
          | goto | text | NO | | NULL | |
          | domain | varchar(255) | NO | MUL | NULL | |
          | created | datetime | NO | | 0000-00-00 00:00:00 | |
          | modified | datetime | NO | | 0000-00-00 00:00:00 | |
          | active | tinyint(1) | NO | | 1 | |
          +----------+--------------+------+-----+---------------------+-------+
        • /dev/rob0
          ... pickup(8) picks up mail which was sent via sendmail(1). This is a local/system user s process (UID 5005, specifically) sending the mail. Your
          Message 4 of 28 , Feb 8, 2013
            On Fri, Feb 08, 2013 at 04:06:57PM +0100, Titanus Eramius wrote:
            > Please note that the last time I asked about the behavior of Postfix it
            > turned out I had misunderstood the concept of relaying mail. It might
            > be the case again.
            >
            > I'm running the mailserver that serves this domain + a few others,
            > the mailserver at ubuntudanmark.dk and the mailservers at nt-data.dk.
            >
            > So I'm running these servers, with this relation:
            > mx01.aptget.dk <-- Not a backup MX
            > mx01.ubuntudanmark.dk <-- Not a backup MX
            > mx01.nt-data.dk <-- Backup MX for mx01.aptget.dk and
            > mx01.ubuntudanmark.dk
            > mx02.nt-data.dk <-- Backup MX for mx01.nt-data.dk
            >
            > The setup is entirely virtual, using MySQL to store aliases, addressees
            > etc. The problem is, that *I think* the backup MX' can be used to
            > spread backscatter. I routinely looks at the Postfix logging, and found
            > these entries yesterday from mx01.nt-data.dk:
            >
            > ---
            > titanus@ntdata:/var/log$ grep "048341743609" mail.log.1
            >
            > Feb 7 22:12:48 ntdata postfix/pickup[24843]: 048341743609: uid=5005
            > from=<SRS0=3u76=L7=gmail.com=jimmiedcu949@...>

            pickup(8) picks up mail which was sent via sendmail(1). This is a
            local/system user's process (UID 5005, specifically) sending the
            mail. Your misunderstanding this time seems to be that you think it
            came from the network and could thus be rejected.

            If this seems to be some kind of abuse, it could be that something
            you're running on the server has been compromised; web/php scripts
            being the most common vector.

            > Feb 7 22:12:48 ntdata postfix/cleanup[30176]: 048341743609:
            > message-id=<GI63Z8-USKQ93-NH@...>
            >
            > Feb 7 22:12:48 ntdata postfix/qmgr[20252]: 048341743609:
            > from=<SRS0=3u76=L7=gmail.com=jimmiedcu949@...>, size=5268,
            > nrcpt=1 (queue active)
            >
            > Feb 7 22:12:48 ntdata postfix/smtp[30181]: 048341743609:
            > to=<acer@...>,
            > relay=mx01.ubuntudanmark.dk[31.192.231.5]:25, delay=0.71,
            > delays=0/0.04/0.17/0.5, dsn=5.1.1, status=bounced (host
            > mx01.ubuntudanmark.dk[31.192.231.5] said: 550 5.1.1
            > <acer@...>: Recipient address rejected: User unknown in
            > virtual mailbox table (in reply to RCPT TO command))
            >
            > Feb 7 22:12:48 ntdata postfix/bounce[30182]: 048341743609: sender
            > non-delivery notification: B201D1743608
            >
            > Feb 7 22:12:48 ntdata postfix/qmgr[20252]: 048341743609: removed
            > ---
            >
            > Then mx01.nt-data.dk tries to send a bounce to gmail:
            >
            > ---
            > Feb 7 22:12:52 ntdata postfix/smtp[30183]: B201D1743608:
            > to=<jimmiedcu949@...>,
            > orig_to=<SRS0=3u76=L7=gmail.com=jimmiedcu949@...>,

            Here you have virtually aliased this sender (now a bounce recipient)
            address to jimmiedcu949@....

            > relay=gmail-smtp-in.l.google.com[173.194.71.26]:25, delay=3.4,
            > delays=0.01/0.01/0.29/3, dsn=5.1.1, status=bounced (host
            > gmail-smtp-in.l.google.com[173.194.71.26] said: 550-5.1.1 The email
            > account that you tried to reach does not exist. Please try 550-5.1.1
            > double-checking the recipient's email address for typos or 550-5.1.1
            > unnecessary spaces. Learn more at 550 5.1.1
            > http://support.google.com/mail/bin/answer.py?answer=6596
            > bc7si9536557lbb.184 - gsmtp (in reply to RCPT TO command))
            > ---
            >
            > The address acer@... does not exist - Neither at
            > mx01.nt-data.dk nor at mx01.ubuntudanmark.dk, so I would like
            > mx01.nt-data.dk to reject messages to it. I've tried with other
            > non-existent addresses trough telnet, and mx01.nt-data.dk accepts them,
            > as long as they are to one of the backup domains, and then bounces them
            > (so currently they are disabled in the database).

            There is no possible mechanism within Postfix to reject mail
            submitted via the sendmail command.

            > Following is postconf -n, the content of the 2 relay_* MySQL-files, and
            > the structure of their database. If more is needed, then please let me
            > know and I'll include it.
            >
            > Any pointers, examples or explanations will be appreciated. I've read
            > in the documentation for virtual hosting and backup MX', but the answer
            > seems to evades me.

            FWIW, generally a backup MX is a bad idea. Why did you want it?

            [snip]
            --
            http://rob0.nodns4.us/ -- system administration and consulting
            Offlist GMX mail is seen only if "/dev/rob0" is in the Subject:
          • Titanus Eramius
            Fri, 8 Feb 2013 09:45:07 -0600 skrev /dev/rob0 : snip ... I m sorry, UID 5005 is SpamAssassin. The grep-command didn t got all ... Feb 7
            Message 5 of 28 , Feb 8, 2013
              Fri, 8 Feb 2013 09:45:07 -0600 skrev /dev/rob0 <rob0@...>:

              snip
              > > ---
              > > titanus@ntdata:/var/log$ grep "048341743609" mail.log.1
              > >
              > > Feb 7 22:12:48 ntdata postfix/pickup[24843]: 048341743609: uid=5005
              > > from=<SRS0=3u76=L7=gmail.com=jimmiedcu949@...>
              >
              > pickup(8) picks up mail which was sent via sendmail(1). This is a
              > local/system user's process (UID 5005, specifically) sending the
              > mail. Your misunderstanding this time seems to be that you think it
              > came from the network and could thus be rejected.
              >
              > If this seems to be some kind of abuse, it could be that something
              > you're running on the server has been compromised; web/php scripts
              > being the most common vector.

              I'm sorry, UID 5005 is SpamAssassin. The grep-command didn't got all
              the lines, so here they are:
              ---
              Feb 7 22:12:46 ntdata postfix/smtpd[30171]: connect from
              c-50-151-186-224.hsd1.in.comcast.net[50.151.186.224]

              Feb 7 22:12:47 ntdata postfix/smtpd[30171]: 39E441743607:
              client=c-50-151-186-224.hsd1.in.comcast.net[50.151.186.224]

              Feb 7 22:12:47 ntdata postfix/cleanup[30176]: 39E441743607:
              message-id=<GI63Z8-USKQ93-NH@...>

              Feb 7 22:12:47 ntdata postfix/qmgr[20252]: 39E441743607:
              from=<SRS0=3u76=L7=gmail.com=jimmiedcu949@...>, size=2182,
              nrcpt=1 (queue active)

              Feb 7 22:12:47 ntdata spamd[6887]: spamd: connection from
              localhost.localdomain [127.0.0.1] at port 58896 Feb 7 22:12:47 ntdata
              spamd[6887]: spamd: processing message
              <GI63Z8-USKQ93-NH@...> for
              acer@...:5005

              Feb 7 22:12:47 ntdata postfix/smtpd[30171]:
              disconnect from c-50-151-186-224.hsd1.in.comcast.net[50.151.186.224]

              Feb 7 22:12:48 ntdata spamd[6887]: spamd: identified spam (11.6/5.0)
              for acer@...:5005 in 0.4 seconds, 2200 bytes.

              Feb 7 22:12:48 ntdata spamd[6887]: spamd: result: Y 11 -
              FH_HELO_EQ_D_D_D_D,HELO_DYNAMIC_IPADDR,RCVD_IN_BRBL_LASTEXT,RCVD_IN_PBL,RCVD_IN_XBL,RDNS_DYNAMIC,SPF_FAIL
              scantime=0.4,size=2200,user=acer@...,uid=5005,required_score=5.0,rhost=localhost.localdomain,raddr=127.0.0.1,rport=58896,mid=<GI63Z8-USKQ93-NH@...>,autolearn=no

              Feb 7 22:12:48 ntdata postfix/pickup[24843]: 048341743609: uid=5005
              from=<SRS0=3u76=L7=gmail.com=jimmiedcu949@...>

              Feb 7 22:12:48 ntdata postfix/pipe[30177]: 39E441743607:
              to=<acer@...>, relay=spamassassin, delay=0.95,
              delays=0.53/0/0/0.41, dsn=2.0.0, status=sent (delivered via
              spamassassin service)

              Feb 7 22:12:48 ntdata postfix/qmgr[20252]: 39E441743607: removed

              Feb 7 22:12:48 ntdata postfix/cleanup[30176]: 048341743609:
              message-id=<GI63Z8-USKQ93-NH@...>

              Feb 7 22:12:48 ntdata postfix/qmgr[20252]: 048341743609:
              from=<SRS0=3u76=L7=gmail.com=jimmiedcu949@...>, size=5268,
              nrcpt=1 (queue active)

              Feb 7 22:12:48 ntdata spamd[6886]: prefork: child states: II

              Feb 7 22:12:48 ntdata postfix/smtp[30181]: certificate verification
              failed for mx01.ubuntudanmark.dk[31.192.231.5]:25: self-signed
              certificate

              Feb 7 22:12:48 ntdata postfix/smtp[30181]: 048341743609:
              to=<acer@...>,
              relay=mx01.ubuntudanmark.dk[31.192.231.5]:25, delay=0.71,
              delays=0/0.04/0.17/0.5, dsn=5.1.1, status=bounced (host
              mx01.ubuntudanmark.dk[31.192.231.5] said: 550 5.1.1
              <acer@...>: Recipient address rejected: User unknown in
              virtual mailbox table (in reply to RCPT TO command))

              Feb 7 22:12:48 ntdata postfix/cleanup[30176]: B201D1743608:
              message-id=<20130207211248.B201D1743608@...-data.dk>

              Feb 7 22:12:48 ntdata postfix/bounce[30182]: 048341743609: sender
              non-delivery notification: B201D1743608

              Feb 7 22:12:48 ntdata postfix/qmgr[20252]: B201D1743608: from=<>,
              size=7699, nrcpt=1 (queue active)

              Feb 7 22:12:48 ntdata postfix/qmgr[20252]: 048341743609: removed

              Feb 7 22:12:49 ntdata postfix/smtp[30183]: certificate verification
              failed for gmail-smtp-in.l.google.com[173.194.71.26]:25: untrusted
              issuer /C=US/O=Equifax/OU=Equifax Secure Certificate Authority

              Feb 7 22:12:52 ntdata postfix/smtp[30183]: B201D1743608:
              to=<jimmiedcu949@...>,
              orig_to=<SRS0=3u76=L7=gmail.com=jimmiedcu949@...>,
              relay=gmail-smtp-in.l.google.com[173.194.71.26]:25, delay=3.4,
              delays=0.01/0.01/0.29/3, dsn=5.1.1, status=bounced (host
              gmail-smtp-in.l.google.com[173.194.71.26] said: 550-5.1.1 The email
              account that you tried to reach does not exist. Please try 550-5.1.1
              double-checking the recipient's email address for typos or 550-5.1.1
              unnecessary spaces. Learn more at 550 5.1.1
              http://support.google.com/mail/bin/answer.py?answer=6596
              bc7si9536557lbb.184 - gsmtp (in reply to RCPT TO command))

              Feb 7 22:12:52 ntdata postfix/qmgr[20252]: B201D1743608: removed
              ---

              snip

              >
              > FWIW, generally a backup MX is a bad idea. Why did you want it?
              >
              > [snip]

              Yeah, I start to see why. nt-data is my (soon to be) hosting company,
              and when handling other peoples mail, I think it's wise to have some
              sort of a backup system in place.

              I've been searching high and low for alternatives, but short of setting
              something fancy up there don't seem to be any.

              Thank you for the reply.
            • Jeroen Geilman
              ... So you are...not re-injecting spamassassin traffic, but instead re-submitting it via sendmail ? That s weird. ... THIS is a send to spamassassin, but
              Message 6 of 28 , Feb 8, 2013
                On 02/08/2013 06:02 PM, Titanus Eramius wrote:

                > Feb 7 22:12:48 ntdata postfix/pickup[24843]: 048341743609: uid=5005
                > from=<SRS0=3u76=L7=gmail.com=jimmiedcu949@...>

                So you are...not re-injecting spamassassin traffic, but instead
                re-submitting it via sendmail ?
                That's weird.

                > Feb 7 22:12:48 ntdata postfix/pipe[30177]: 39E441743607:
                > to=<acer@...>, relay=spamassassin, delay=0.95,
                > delays=0.53/0/0/0.41, dsn=2.0.0, status=sent (delivered via
                > spamassassin service)

                THIS is a send to spamassassin, but delayed in logging for almost a second.

                It looks very much as if you're doing in-line spamassassin checks, but
                then not re-injecting it via SMTP.

                Why are you doing such a strange thing ?


                --
                J.
              • Titanus Eramius
                ... To be honest I ve read quite a lot about Postfix, Dovecot, SA ... , but my experience is very limited and contained to about 3 months of running time. So
                Message 7 of 28 , Feb 9, 2013
                  Fri, 08 Feb 2013 21:54:02 +0100 skrev Jeroen Geilman <jeroen@...>:

                  > On 02/08/2013 06:02 PM, Titanus Eramius wrote:
                  >
                  > > Feb 7 22:12:48 ntdata postfix/pickup[24843]: 048341743609: uid=5005
                  > > from=<SRS0=3u76=L7=gmail.com=jimmiedcu949@...>
                  >
                  > So you are...not re-injecting spamassassin traffic, but instead
                  > re-submitting it via sendmail ?
                  > That's weird.
                  >
                  > > Feb 7 22:12:48 ntdata postfix/pipe[30177]: 39E441743607:
                  > > to=<acer@...>, relay=spamassassin, delay=0.95,
                  > > delays=0.53/0/0/0.41, dsn=2.0.0, status=sent (delivered via
                  > > spamassassin service)
                  >
                  > THIS is a send to spamassassin, but delayed in logging for almost a
                  > second.
                  >
                  > It looks very much as if you're doing in-line spamassassin checks,
                  > but then not re-injecting it via SMTP.
                  >
                  > Why are you doing such a strange thing ?
                  >

                  To be honest I've read quite a lot about Postfix, Dovecot, SA ... , but
                  my experience is very limited and contained to about 3 months of
                  running time.

                  So SA is integrated as I found best after reading docs and guides, and
                  it's more than likely it can be done in a better way. Normally though,
                  the running time of SA is around ~200ms per text-mail.

                  It's integrated as a content_filter on smtp like so:
                  smtp inet n - - - - smtpd -o content_filter=spamassassin

                  And then on it's own lines:
                  spamassassin unix - n n - - pipe
                  flags=Rq user=spamd argv=/usr/bin/spamc -u ${user}@${domain}
                  -e /usr/sbin/sendmail -oi -f ${sender} ${recipient}

                  The sendmail-method seems to be preferred by the SA-folks
                  https://wiki.apache.org/spamassassin/IntegratedSpamdInPostfix

                  All of those examples uses sendmail. But again, in relation to Postfix,
                  it might very well be possible to integrate SA in a better way. Maybe
                  the method suggested by the docs on content_filters?
                  http://www.postfix.org/FILTER_README.html#advanced_filter
                • James Griffin
                  ... Integrating SA with amavisd-new is a better approach IMO. You might consider that in your setup? -- Primary Key: 4096R/1D31DC38 2011-12-03 Key Fingerprint:
                  Message 8 of 28 , Feb 9, 2013
                    --> Titanus Eramius <titanus@...> [2013-02-09 12:23:38 +0100]:

                    > All of those examples uses sendmail. But again, in relation to Postfix,
                    > it might very well be possible to integrate SA in a better way. Maybe
                    > the method suggested by the docs on content_filters?
                    > http://www.postfix.org/FILTER_README.html#advanced_filter

                    Integrating SA with amavisd-new is a better approach IMO. You might
                    consider that in your setup?

                    --
                    Primary Key: 4096R/1D31DC38 2011-12-03
                    Key Fingerprint: A4B9 E875 A18C 6E11 F46D B788 BEE6 1251 1D31 DC38
                  • Noel Jones
                    ... Nothing wrong with this setup. It s very easy to configure, requires no third-party software or additional packages, and it s easy to understand where
                    Message 9 of 28 , Feb 9, 2013
                      On 2/9/2013 5:23 AM, Titanus Eramius wrote:
                      > Fri, 08 Feb 2013 21:54:02 +0100 skrev Jeroen Geilman <jeroen@...>:
                      >
                      >> On 02/08/2013 06:02 PM, Titanus Eramius wrote:
                      >>
                      >>> Feb 7 22:12:48 ntdata postfix/pickup[24843]: 048341743609: uid=5005
                      >>> from=<SRS0=3u76=L7=gmail.com=jimmiedcu949@...>
                      >>
                      >> So you are...not re-injecting spamassassin traffic, but instead
                      >> re-submitting it via sendmail ?
                      >> That's weird.
                      >>
                      >>> Feb 7 22:12:48 ntdata postfix/pipe[30177]: 39E441743607:
                      >>> to=<acer@...>, relay=spamassassin, delay=0.95,
                      >>> delays=0.53/0/0/0.41, dsn=2.0.0, status=sent (delivered via
                      >>> spamassassin service)
                      >>
                      >> THIS is a send to spamassassin, but delayed in logging for almost a
                      >> second.
                      >>
                      >> It looks very much as if you're doing in-line spamassassin checks,
                      >> but then not re-injecting it via SMTP.
                      >>
                      >> Why are you doing such a strange thing ?
                      >>
                      >
                      > To be honest I've read quite a lot about Postfix, Dovecot, SA ... , but
                      > my experience is very limited and contained to about 3 months of
                      > running time.
                      >
                      > So SA is integrated as I found best after reading docs and guides, and
                      > it's more than likely it can be done in a better way. Normally though,
                      > the running time of SA is around ~200ms per text-mail.
                      >
                      > It's integrated as a content_filter on smtp like so:
                      > smtp inet n - - - - smtpd -o content_filter=spamassassin
                      >
                      > And then on it's own lines:
                      > spamassassin unix - n n - - pipe
                      > flags=Rq user=spamd argv=/usr/bin/spamc -u ${user}@${domain}
                      > -e /usr/sbin/sendmail -oi -f ${sender} ${recipient}
                      >
                      > The sendmail-method seems to be preferred by the SA-folks
                      > https://wiki.apache.org/spamassassin/IntegratedSpamdInPostfix
                      >
                      > All of those examples uses sendmail. But again, in relation to Postfix,
                      > it might very well be possible to integrate SA in a better way.

                      Nothing wrong with this setup. It's very easy to configure,
                      requires no third-party software or additional packages, and it's
                      easy to understand where your mail goes. I expect that's why it's
                      used as an example on the spamassassin wiki, and doesn't necessarily
                      mean it's the recommended or preferred method.

                      It's not necessarily the highest performance or the most flexible,
                      but if it suits your needs, no need to change.

                      Folks who need more usually pick some third-party filtering software
                      that can run pre-queue as an smtpd_proxy_filter or milter. These
                      are, without exception, more complicated than the setup you
                      currently have. The big advantage of a pre-queue filter is you can
                      safely REJECT unwanted mail.

                      Amavisd-new is a popular choice for pre-queue filtering since it's
                      fast, reliable, flexible, and can integrate both SpamAssassin and
                      antivirus.


                      -- Noel Jones
                    • Titanus Eramius
                      Sat, 09 Feb 2013 10:25:31 -0600 skrev Noel Jones : ... Sorry for the late response, it took some time to dig through all the
                      Message 10 of 28 , Feb 16, 2013
                        Sat, 09 Feb 2013 10:25:31 -0600 skrev Noel Jones
                        <njones@...>:

                        ...

                        > Nothing wrong with this setup. It's very easy to configure,
                        > requires no third-party software or additional packages, and it's
                        > easy to understand where your mail goes. I expect that's why it's
                        > used as an example on the spamassassin wiki, and doesn't necessarily
                        > mean it's the recommended or preferred method.
                        >
                        > It's not necessarily the highest performance or the most flexible,
                        > but if it suits your needs, no need to change.
                        >
                        > Folks who need more usually pick some third-party filtering software
                        > that can run pre-queue as an smtpd_proxy_filter or milter. These
                        > are, without exception, more complicated than the setup you
                        > currently have. The big advantage of a pre-queue filter is you can
                        > safely REJECT unwanted mail.
                        >
                        > Amavisd-new is a popular choice for pre-queue filtering since it's
                        > fast, reliable, flexible, and can integrate both SpamAssassin and
                        > antivirus.
                        >
                        >
                        > -- Noel Jones

                        Sorry for the late response, it took some time to dig through all the
                        information. The use of pre-queue filtering would solve another problem
                        I've been working on: What to do with mail from (user)blacklisted
                        senders.

                        I plan on upgrading Debians stable Postfix to the current stable
                        version of 2.10 so I may benefit from postscreen, and that will
                        probably be a good time to install amavisd-new as a pre-queue filter.

                        Thank you for the help once again.
                      • DTNX Postmaster
                        ... A possible shortcut to getting postscreen is using the 2.9.3 version available in the Debian backports repository. That s what we currently use, instead of
                        Message 11 of 28 , Feb 16, 2013
                          On Feb 16, 2013, at 12:18, Titanus Eramius <titanus@...> wrote:

                          > I plan on upgrading Debians stable Postfix to the current stable
                          > version of 2.10 so I may benefit from postscreen, and that will
                          > probably be a good time to install amavisd-new as a pre-queue filter.
                          >
                          > Thank you for the help once again.

                          A possible shortcut to getting postscreen is using the 2.9.3 version
                          available in the Debian backports repository. That's what we currently
                          use, instead of building custom packages.

                          HTH,
                          Jona
                        • Titanus Eramius
                          Sat, 16 Feb 2013 12:39:24 +0100 skrev DTNX Postmaster ... Thank you for pointing the obvious out. I don t know why I didn t thought of backports, but I will
                          Message 12 of 28 , Feb 16, 2013
                            Sat, 16 Feb 2013 12:39:24 +0100 skrev DTNX Postmaster
                            <postmaster@...>:

                            > On Feb 16, 2013, at 12:18, Titanus Eramius <titanus@...> wrote:
                            >
                            > > I plan on upgrading Debians stable Postfix to the current stable
                            > > version of 2.10 so I may benefit from postscreen, and that will
                            > > probably be a good time to install amavisd-new as a pre-queue
                            > > filter.
                            > >
                            > > Thank you for the help once again.
                            >
                            > A possible shortcut to getting postscreen is using the 2.9.3 version
                            > available in the Debian backports repository. That's what we
                            > currently use, instead of building custom packages.
                            >
                            > HTH,
                            > Jona
                            >

                            Thank you for pointing the obvious out.
                            I don't know why I didn't thought of backports, but I will surely be
                            using 2.9.3 from there instead of building from source.
                          • Titanus Eramius
                            Thinking about this, I might have been to specific in my question. At the fundamental level I would like to have 2 or more Postfix servers capable of receiving
                            Message 13 of 28 , Feb 19, 2013
                              Thinking about this, I might have been to specific in my question.

                              At the fundamental level I would like to have 2 or more Postfix servers
                              capable of receiving virtual mail for multiple domains, where one of
                              the servers also handles relaying and local delivery. The rest should
                              function as backup MX.

                              I've tried with relay_domains, but it matches on domain-level which is
                              too much. I then applied relay_recipient_maps, but it don't seem to
                              have any effect, which means that addresses is still matched on domain
                              basis.

                              Every Postfix will have access to a complete list of recipients
                              through MySQL.

                              So the question becomes two-part:
                              Why can't I get relay_recipient_maps to work?

                              How would you recommend to set up a backup MX?
                              One obvious way is not to do it, but some of the mail is not mine,
                              which is why I at least would like the option to run a backup MX.
                            • Viktor Dukhovni
                              ... http://www.postfix.org/DEBUG_README.html#mail http://www.postfix.org/STANDARD_CONFIGURATION_README.html#backup Wildcard entries in canonical_maps and
                              Message 14 of 28 , Feb 19, 2013
                                On Tue, Feb 19, 2013 at 12:21:35PM +0100, Titanus Eramius wrote:

                                > I've tried with relay_domains, but it matches on domain-level which is
                                > too much. I then applied relay_recipient_maps, but it don't seem to
                                > have any effect, which means that addresses is still matched on domain
                                > basis.
                                >
                                > Every Postfix will have access to a complete list of recipients
                                > through MySQL.
                                >
                                > So the question becomes two-part:
                                > Why can't I get relay_recipient_maps to work?

                                http://www.postfix.org/DEBUG_README.html#mail
                                http://www.postfix.org/STANDARD_CONFIGURATION_README.html#backup

                                Wildcard entries in canonical_maps and virtual_alias_maps are the
                                most common reason for recipient validation failing to distinguish
                                between valid and invalid recipients.

                                --
                                Viktor.
                              • Titanus Eramius
                                Tue, 19 Feb 2013 16:31:05 +0000 skrev Viktor Dukhovni ... Thank you for the response and sorry for the slow reply. The problem seems to be related with the
                                Message 15 of 28 , Mar 22, 2013
                                  Tue, 19 Feb 2013 16:31:05 +0000 skrev Viktor Dukhovni
                                  <postfix-users@...>:

                                  > On Tue, Feb 19, 2013 at 12:21:35PM +0100, Titanus Eramius wrote:
                                  >
                                  > > I've tried with relay_domains, but it matches on domain-level which
                                  > > is too much. I then applied relay_recipient_maps, but it don't seem
                                  > > to have any effect, which means that addresses is still matched on
                                  > > domain basis.
                                  > >
                                  > > Every Postfix will have access to a complete list of recipients
                                  > > through MySQL.
                                  > >
                                  > > So the question becomes two-part:
                                  > > Why can't I get relay_recipient_maps to work?
                                  >
                                  > http://www.postfix.org/DEBUG_README.html#mail
                                  > http://www.postfix.org/STANDARD_CONFIGURATION_README.html#backup
                                  >
                                  > Wildcard entries in canonical_maps and virtual_alias_maps are the
                                  > most common reason for recipient validation failing to distinguish
                                  > between valid and invalid recipients.
                                  >

                                  Thank you for the response and sorry for the slow reply.

                                  The problem seems to be related with the virtual setup, but I'm not
                                  sure how to best describe and document it.

                                  Besides aptget.dk this server also hosts cogky.dk (among others), and
                                  while unknown recipients is being correctly rejected with a 550 when
                                  sent to aptget.dk, they are not when sent to the other virtual domains.
                                  Instead they are accepted and then returned by the MAILER_DAEMON, which
                                  in turn opens the server to backscatter.

                                  I have tried setting "local_recipient_maps = $virtual_mailbox_maps"
                                  in main.cf, but without any apparent effect. To be honest, I'm unsure if
                                  I have set "virtual_mailbox_maps" correct, but when testing it with
                                  postalias it seems to work
                                  titanus@aptget:/etc/postfix$ sudo postalias -q titanus@...
                                  mysql:/etc/postfix/mysql_virtual_mailbox_maps.cf
                                  aptget.dk/titanus/

                                  When I test mysql_virtual_mailbox_maps.cf with a non-existent address,
                                  nothing is returned and the exit status is 1.

                                  What I would like to achieve, is that Postfix rejects mail to
                                  non-existent recipients before accepting mail.

                                  Thanks again, Titanus


                                  postconf -n
                                  alias_maps = hash:/etc/aliases

                                  bounce_template_file = /etc/postfix/bounce.cf

                                  broken_sasl_auth_clients = yes

                                  config_directory = /etc/postfix

                                  delay_warning_time = 4

                                  disable_vrfy_command = yes

                                  dovecot_destination_recipient_limit = 1

                                  inet_interfaces = 46.21.105.38

                                  local_recipient_maps = $virtual_mailbox_maps

                                  mailman_destination_recipient_limit = 1

                                  maximal_queue_lifetime = 15

                                  message_size_limit = 26214400

                                  mydestination = localhost

                                  mydomain = aptget.dk

                                  myhostname = aptget.aptget.dk

                                  mynetworks = 127.0.0.0/8

                                  postscreen_dnsbl_action = enforce

                                  postscreen_dnsbl_sites = truncate.gbudb.net*2 b.barracudacentral.org*1
                                  zen.spamhaus.org*1 bl.spamcop.net*1

                                  postscreen_dnsbl_threshold = 2

                                  postscreen_greet_action = enforce

                                  recipient_canonical_classes = envelope_recipient

                                  recipient_canonical_maps = hash:/etc/postfix/pfix-no-srs.cf,
                                  tcp:127.0.0.1:10002

                                  sender_canonical_classes = envelope_sender

                                  sender_canonical_maps = hash:/etc/postfix/pfix-no-srs.cf,
                                  tcp:127.0.0.1:10001

                                  smtp_tls_security_level = may

                                  smtp_tls_session_cache_database =
                                  btree:$data_directory/smtp_tls_session_cache

                                  smtpd_data_restrictions = reject_unauth_pipelining,
                                  reject_multi_recipient_bounce,

                                  smtpd_helo_required = yes

                                  smtpd_recipient_restrictions = reject_non_fqdn_sender,
                                  reject_non_fqdn_recipient, reject_unknown_sender_domain,
                                  reject_unknown_recipient_domain, reject_unauth_destination,

                                  smtpd_sasl_auth_enable = yes

                                  smtpd_sasl_exceptions_networks = $mynetworks

                                  smtpd_sasl_path = private/auth

                                  smtpd_sasl_security_options = noanonymous

                                  smtpd_sasl_type = dovecot

                                  smtpd_tls_ask_ccert = yes

                                  smtpd_tls_cert_file = /etc/ssl/self-signed/smtpd.crt

                                  smtpd_tls_key_file = /etc/ssl/self-signed/smtpd.key

                                  smtpd_tls_loglevel = 1

                                  smtpd_tls_received_header = yes

                                  smtpd_tls_security_level = may

                                  smtpd_tls_session_cache_database =
                                  btree:$data_directory/smtpd_tls_session_cache

                                  spamassassin_destination_recipient_limit = 1

                                  tls_random_source = dev:/dev/urandom

                                  transport_maps = hash:/etc/postfix/transport.cf

                                  virtual_alias_maps =
                                  proxy:mysql:/etc/postfix/mysql_virtual_alias_maps.cf

                                  virtual_gid_maps = static:5000

                                  virtual_mailbox_base = /home/vmail

                                  virtual_mailbox_domains =
                                  proxy:mysql:/etc/postfix/mysql_virtual_domains_maps.cf

                                  virtual_mailbox_maps =
                                  proxy:mysql:/etc/postfix/mysql_virtual_mailbox_maps.cf

                                  virtual_transport = dovecot

                                  virtual_uid_maps = static:5000
                                • Wietse Venema
                                  ... Where is cogky.dk defined: mydestination, virtual_alias_domains, virtual_mailbox_domains, relay_domains? It must be only one. This answer determines where
                                  Message 16 of 28 , Mar 22, 2013
                                    Titanus Eramius:
                                    > Besides aptget.dk this server also hosts cogky.dk (among others), and
                                    > while unknown recipients is being correctly rejected with a 550 when
                                    > sent to aptget.dk, they are not when sent to the other virtual domains.
                                    > Instead they are accepted and then returned by the MAILER_DAEMON, which
                                    > in turn opens the server to backscatter.

                                    Where is cogky.dk defined: mydestination, virtual_alias_domains,
                                    virtual_mailbox_domains, relay_domains? It must be only one.

                                    This answer determines where the "known" recipients must be listed:
                                    local_recipient_maps, virtual_alias_maps,m virtual_mailbox_maps,
                                    relay_recipients. If you list the domain or recipients in the wrong
                                    place then mail will be rejected.

                                    See http://www.postfix.org/ADDRESS_CLASS_README.html

                                    Wietse
                                  • Titanus Eramius
                                    Fri, 22 Mar 2013 16:55:21 -0400 (EDT) skrev Wietse Venema ... The goal is a virtual only mailserver, so the domains is stored in MySQL and fetched through
                                    Message 17 of 28 , Mar 22, 2013
                                      Fri, 22 Mar 2013 16:55:21 -0400 (EDT) skrev Wietse Venema
                                      <wietse@...>:

                                      > Titanus Eramius:
                                      > > Besides aptget.dk this server also hosts cogky.dk (among others),
                                      > > and while unknown recipients is being correctly rejected with a 550
                                      > > when sent to aptget.dk, they are not when sent to the other virtual
                                      > > domains. Instead they are accepted and then returned by the
                                      > > MAILER_DAEMON, which in turn opens the server to backscatter.
                                      >
                                      > Where is cogky.dk defined: mydestination, virtual_alias_domains,
                                      > virtual_mailbox_domains, relay_domains? It must be only one.
                                      >
                                      > This answer determines where the "known" recipients must be listed:
                                      > local_recipient_maps, virtual_alias_maps,m virtual_mailbox_maps,
                                      > relay_recipients. If you list the domain or recipients in the wrong
                                      > place then mail will be rejected.
                                      >
                                      > See http://www.postfix.org/ADDRESS_CLASS_README.html
                                      >
                                      > Wietse

                                      The goal is a "virtual only" mailserver, so the domains is stored
                                      in MySQL and fetched through virtual_mailbox_domains. Besides
                                      virtual_mailbox_domains, I use virtual_mailbox_maps and
                                      virtual_alias_maps.

                                      The documentation is among the best documentation I have seen, but I
                                      can't seem to find the solution, even though I have read most of what I
                                      could find in relation to virtual handling.

                                      One more "clue" is the error messages when sending to non-existent
                                      users. When sending to aptget.dk Postfix responds with
                                      "550 5.1.1 <non_existent@...>: Recipient address rejected: User
                                      unknown in virtual mailbox table".

                                      When sending to cogky.dk the response is only "<non_existent@...>:
                                      user unknown"

                                      Thank you for your time, Titanus
                                    • Wietse Venema
                                      ... With the domain defined in virtual_mailbox_domains, mail will fail with user unknown in virtual mailbox table when the recipient is not found in
                                      Message 18 of 28 , Mar 22, 2013
                                        Titanus Eramius:
                                        > Fri, 22 Mar 2013 16:55:21 -0400 (EDT) skrev Wietse Venema
                                        > > Where is cogky.dk defined: mydestination, virtual_alias_domains,
                                        > > virtual_mailbox_domains, relay_domains? It must be only one.
                                        > >
                                        > > This answer determines where the "known" recipients must be listed:
                                        > > local_recipient_maps, virtual_alias_maps,m virtual_mailbox_maps,
                                        > > relay_recipients. If you list the domain or recipients in the wrong
                                        > > place then mail will be rejected.
                                        > >
                                        > > See http://www.postfix.org/ADDRESS_CLASS_README.html
                                        >
                                        > The goal is a "virtual only" mailserver, so the domains is stored
                                        > in MySQL and fetched through virtual_mailbox_domains. Besides
                                        > virtual_mailbox_domains, I use virtual_mailbox_maps and
                                        > virtual_alias_maps.

                                        With the domain defined in virtual_mailbox_domains, mail will fail
                                        with "user unknown in virtual mailbox table" when the recipient is
                                        not found in virtual_mailbox_maps. This is described in agonizing
                                        detail in ADDRESS_CLASS_README.

                                        Test your lookups:

                                        postmap -q cogky.dk the-virtual_mailbox_domains-table
                                        This should return a result (the value does not matter).

                                        postmap -q real-user@... the-virtual_mailbox_maps-table
                                        This should return a result (the mailbox file name).

                                        postmap -q bogus-user@... the-virtual_mailbox_maps-table
                                        This should return no result (Postfix treats this as "user unknown
                                        in virtual mailbox table").

                                        Wietse
                                      • mouss
                                        ... one possible reason is that you configured a wildcard alias: @cogky.dk == @aptget.dk (that is anything to cogky maps to same address in aptget.dk). if so,
                                        Message 19 of 28 , Mar 24, 2013
                                          Le 23/03/2013 00:02, Titanus Eramius a écrit :
                                          > [snip]
                                          > The goal is a "virtual only" mailserver, so the domains is stored
                                          > in MySQL and fetched through virtual_mailbox_domains. Besides
                                          > virtual_mailbox_domains, I use virtual_mailbox_maps and
                                          > virtual_alias_maps.
                                          >
                                          > The documentation is among the best documentation I have seen, but I
                                          > can't seem to find the solution, even though I have read most of what I
                                          > could find in relation to virtual handling.
                                          >
                                          > One more "clue" is the error messages when sending to non-existent
                                          > users. When sending to aptget.dk Postfix responds with
                                          > "550 5.1.1 <non_existent@...>: Recipient address rejected: User
                                          > unknown in virtual mailbox table".
                                          >
                                          > When sending to cogky.dk the response is only "<non_existent@...>:
                                          > user unknown"
                                          >

                                          one possible reason is that you configured a wildcard alias:
                                          @... ==> @...
                                          (that is anything to cogky maps to same address in aptget.dk).

                                          if so, that's your problem. you need to configure mappings only for
                                          existing users.
                                          since you use mysql, this should be easy to do.
                                        • Titanus Eramius
                                          Fri, 22 Mar 2013 19:12:40 -0400 (EDT) skrev Wietse Venema ... aptget:~# postalias -q cogky.dk mysql:/etc/postfix/mysql_virtual_mailbox_domains.cf cogky.dk ...
                                          Message 20 of 28 , Mar 25, 2013
                                            Fri, 22 Mar 2013 19:12:40 -0400 (EDT) skrev Wietse Venema
                                            <wietse@...>:

                                            > Test your lookups:
                                            >
                                            > postmap -q cogky.dk the-virtual_mailbox_domains-table
                                            > This should return a result (the value does not matter).

                                            aptget:~# postalias -q cogky.dk
                                            mysql:/etc/postfix/mysql_virtual_mailbox_domains.cf
                                            cogky.dk

                                            > postmap -q real-user@... the-virtual_mailbox_maps-table
                                            > This should return a result (the mailbox file name).

                                            aptget:~# postalias -q real-user@...
                                            mysql:/etc/postfix/mysql_virtual_mailbox_maps.cf
                                            cogky.dk/real-user/

                                            > postmap -q bogus-user@... the-virtual_mailbox_maps-table
                                            > This should return no result (Postfix treats this as "user unknown
                                            > in virtual mailbox table").

                                            And this does not return a result. Bash gives a error-status of 1.


                                            Sun, 24 Mar 2013 09:36:03 +0100 skrev mouss <mouss@...>:

                                            > one possible reason is that you configured a wildcard alias:
                                            > @... ==> @...
                                            > (that is anything to cogky maps to same address in aptget.dk).

                                            As far as I can see that should not be the case. All addresses and
                                            aliases in the database have a left hand side to it. Is there a way to
                                            test this?


                                            I'm using Dovecot 2 as LDA for final delivery and IMAP-services, so
                                            "virtual_transport" is set to "dovecot" in main.cf and the following
                                            lines are in master.cf:

                                            dovecot unix - n n - - pipe
                                            flags=DRhu user=vmail:vmail argv=/usr/lib/dovecot/deliver -d
                                            ${recipient}


                                            When looking through the log, it looks like the "user unknown"
                                            response comes from Dovecot and not Postfix:

                                            Mar 25 13:43:53 aptget postfix/smtpd[24133]: connect from
                                            unknown[92.243.255.38]

                                            Mar 25 13:43:54 aptget postfix/smtpd[24133]:
                                            Anonymous TLS connection established from unknown[92.243.255.38]: TLSv1
                                            with cipher DHE-RSA-AES128-SHA (128/128 bits)

                                            Mar 25 13:43:54 aptget dovecot: auth-worker(24136): mysql(localhost):
                                            Connected to database postfix

                                            Mar 25 13:43:54 aptget postfix/smtpd[24133]: BB6AD371DDC4:
                                            client=unknown[92.243.255.38], sasl_method=LOGIN,
                                            sasl_username=HIDDEN_USER@...

                                            Mar 25 13:43:54 aptget postfix-policyd: connection from: 127.0.0.1
                                            port: 48937 slots: 0 of 4096 used

                                            Mar 25 13:43:54 aptget postfix-policyd: connecting to mysql database:
                                            localhost

                                            Mar 25 13:43:54 aptget postfix-policyd: connected..

                                            Mar 25 13:43:54 aptget postfix-policyd: rcpt=16, throttle=clear(a),
                                            host=92.243.255.38, from=titanus@..., to=unknown-user@...,
                                            size=365/26214400, quota=365/1800000000, count=1/125(10),
                                            rcpt=1/600(11), threshold=0%|0%|0%, sasl_username=HIDDEN_USER@...

                                            Mar 25 13:43:54 aptget postfix/cleanup[24138]: BB6AD371DDC4:
                                            message-id=<20130325134351.5c2e026f@...>

                                            Mar 25 13:43:54 aptget postfix/qmgr[23982]: BB6AD371DDC4:
                                            from=<titanus@...>, size=663, nrcpt=1 (queue active)

                                            Mar 25 13:43:55 aptget postfix/pipe[24140]: BB6AD371DDC4:
                                            to=<unknown-user@...>, relay=dovecot, delay=0.38,
                                            delays=0.26/0.03/0/0.09, dsn=5.1.1, status=bounced (user unknown)

                                            Mar 25 13:43:55 aptget postfix/cleanup[24138]: 16228371DE3E:
                                            message-id=<20130325124355.16228371DE3E@...>

                                            Mar 25 13:43:55 aptget postfix/bounce[24142]: BB6AD371DDC4: sender
                                            non-delivery notification: 16228371DE3E

                                            Mar 25 13:43:55 aptget postfix/qmgr[23982]: 16228371DE3E: from=<>,
                                            size=2673, nrcpt=1 (queue active)

                                            Mar 25 13:43:55 aptget postfix/qmgr[23982]: BB6AD371DDC4: removed

                                            Mar 25 13:43:55 aptget postfix/smtpd[24133]: disconnect from
                                            unknown[92.243.255.38]


                                            Thank you again for helping
                                            Titanus


                                            postconf -n
                                            alias_maps = hash:/etc/aliases

                                            bounce_template_file = /etc/postfix/bounce.cf

                                            broken_sasl_auth_clients = yes

                                            config_directory = /etc/postfix

                                            delay_warning_time = 4

                                            disable_vrfy_command = yes

                                            dovecot_destination_recipient_limit = 1

                                            inet_interfaces = 46.21.105.38

                                            local_recipient_maps = $virtual_mailbox_maps

                                            mailman_destination_recipient_limit = 1

                                            maximal_queue_lifetime = 15

                                            message_size_limit = 26214400

                                            mydestination = localhost

                                            mydomain = aptget.dk

                                            myhostname = aptget.aptget.dk

                                            mynetworks = 127.0.0.0/8

                                            postscreen_dnsbl_action = enforce
                                            postscreen_dnsbl_sites = truncate.gbudb.net*2 b.barracudacentral.org*1
                                            zen.spamhaus.org*1 bl.spamcop.net*1

                                            postscreen_dnsbl_threshold = 2

                                            postscreen_greet_action = enforce

                                            recipient_canonical_classes = envelope_recipient

                                            recipient_canonical_maps = hash:/etc/postfix/pfix-no-srs.cf,
                                            tcp:127.0.0.1:10002

                                            sender_canonical_classes = envelope_sender

                                            sender_canonical_maps = hash:/etc/postfix/pfix-no-srs.cf,
                                            tcp:127.0.0.1:10001

                                            smtp_tls_security_level = may

                                            smtp_tls_session_cache_database =
                                            btree:$data_directory/smtp_tls_session_cache

                                            smtpd_data_restrictions = reject_unauth_pipelining,
                                            reject_multi_recipient_bounce,

                                            smtpd_helo_required = yes

                                            smtpd_recipient_restrictions = reject_non_fqdn_sender,
                                            reject_non_fqdn_recipient, reject_unknown_sender_domain,
                                            reject_unknown_recipient_domain, reject_unauth_destination,

                                            smtpd_sasl_auth_enable = yes

                                            smtpd_sasl_exceptions_networks = $mynetworks

                                            smtpd_sasl_path = private/auth

                                            smtpd_sasl_security_options = noanonymous

                                            smtpd_sasl_type = dovecot

                                            smtpd_tls_ask_ccert = yes

                                            smtpd_tls_cert_file = /etc/ssl/self-signed/smtpd.crt

                                            smtpd_tls_key_file = /etc/ssl/self-signed/smtpd.key

                                            smtpd_tls_loglevel = 1

                                            smtpd_tls_received_header = yes

                                            smtpd_tls_security_level = may

                                            smtpd_tls_session_cache_database =
                                            btree:$data_directory/smtpd_tls_session_cache

                                            spamassassin_destination_recipient_limit = 1

                                            tls_random_source = dev:/dev/urandom

                                            transport_maps = hash:/etc/postfix/transport.cf

                                            virtual_alias_maps =
                                            proxy:mysql:/etc/postfix/mysql_virtual_alias_maps.cf

                                            virtual_gid_maps = static:5000

                                            virtual_mailbox_base = /home/vmail

                                            virtual_mailbox_domains =
                                            proxy:mysql:/etc/postfix/mysql_virtual_domains_maps.cf

                                            virtual_mailbox_maps =
                                            proxy:mysql:/etc/postfix/mysql_virtual_mailbox_maps.cf

                                            virtual_transport = dovecot

                                            virtual_uid_maps = static:5000
                                          • Wietse Venema
                                            ... OK, the table is working as it should. Now let s find out why the bogus recipient is accepted: Next step: - Connect to the public (not content
                                            Message 21 of 28 , Mar 25, 2013
                                              Titanus Eramius:
                                              > Fri, 22 Mar 2013 19:12:40 -0400 (EDT) skrev Wietse Venema
                                              > <wietse@...>:
                                              >
                                              > > Test your lookups:
                                              > >
                                              > > postmap -q cogky.dk the-virtual_mailbox_domains-table
                                              > > This should return a result (the value does not matter).
                                              >
                                              > aptget:~# postalias -q cogky.dk
                                              > mysql:/etc/postfix/mysql_virtual_mailbox_domains.cf
                                              > cogky.dk
                                              >
                                              > > postmap -q real-user@... the-virtual_mailbox_maps-table
                                              > > This should return a result (the mailbox file name).
                                              >
                                              > aptget:~# postalias -q real-user@...
                                              > mysql:/etc/postfix/mysql_virtual_mailbox_maps.cf
                                              > cogky.dk/real-user/
                                              >
                                              > > postmap -q bogus-user@... the-virtual_mailbox_maps-table
                                              > > This should return no result (Postfix treats this as "user unknown
                                              > > in virtual mailbox table").
                                              >
                                              > And this does not return a result. Bash gives a error-status of 1.

                                              OK, the table is working as it should. Now let's find out
                                              why the bogus recipient is accepted:

                                              Next step:

                                              - Connect to the public (not content re-injection) SMTP port and try

                                              $ telnet hostname 25
                                              ehlo ...
                                              mail from:<>
                                              rcpt to:<real-user@...>
                                              rcpt to:<bogus-user@...>
                                              quit

                                              One recipient should be accepted, the other not.

                                              - Same experiment for mail over the submission port, if you have one:

                                              $ openssl s_client -starttls smtp -connect hostname:587
                                              ehlo ...
                                              mail from:<>
                                              rcpt to:<real-user@...>
                                              rcpt to:<bogus-user@...>
                                              quit

                                              This is just in case.

                                              Wietse
                                            • Titanus Eramius
                                              Mon, 25 Mar 2013 11:30:41 -0400 (EDT) skrev Wietse Venema ... Both RCPT TOs are successful titanus@asrock:~$ telnet 46.21.105.38 25 Trying 46.21.105.38...
                                              Message 22 of 28 , Mar 25, 2013
                                                Mon, 25 Mar 2013 11:30:41 -0400 (EDT) skrev Wietse Venema
                                                <wietse@...>:

                                                > Titanus Eramius:
                                                > > Fri, 22 Mar 2013 19:12:40 -0400 (EDT) skrev Wietse Venema
                                                > > <wietse@...>:
                                                > >
                                                > > > Test your lookups:
                                                > > >
                                                > > > postmap -q cogky.dk the-virtual_mailbox_domains-table
                                                > > > This should return a result (the value does not matter).
                                                > >
                                                > > aptget:~# postalias -q cogky.dk
                                                > > mysql:/etc/postfix/mysql_virtual_mailbox_domains.cf
                                                > > cogky.dk
                                                > >
                                                > > > postmap -q real-user@... the-virtual_mailbox_maps-table
                                                > > > This should return a result (the mailbox file name).
                                                > >
                                                > > aptget:~# postalias -q real-user@...
                                                > > mysql:/etc/postfix/mysql_virtual_mailbox_maps.cf
                                                > > cogky.dk/real-user/
                                                > >
                                                > > > postmap -q bogus-user@... the-virtual_mailbox_maps-table
                                                > > > This should return no result (Postfix treats this as "user unknown
                                                > > > in virtual mailbox table").
                                                > >
                                                > > And this does not return a result. Bash gives a error-status of 1.
                                                >
                                                > OK, the table is working as it should. Now let's find out
                                                > why the bogus recipient is accepted:
                                                >
                                                > Next step:
                                                >
                                                > - Connect to the public (not content re-injection) SMTP port and try
                                                >
                                                > $ telnet hostname 25
                                                > ehlo ...
                                                > mail from:<>
                                                > rcpt to:<real-user@...>
                                                > rcpt to:<bogus-user@...>
                                                > quit
                                                >
                                                > One recipient should be accepted, the other not.
                                                >
                                                > - Same experiment for mail over the submission port, if you have one:
                                                >
                                                > $ openssl s_client -starttls smtp -connect hostname:587
                                                > ehlo ...
                                                > mail from:<>
                                                > rcpt to:<real-user@...>
                                                > rcpt to:<bogus-user@...>
                                                > quit
                                                >
                                                > This is just in case.
                                                >
                                                > Wietse

                                                Both RCPT TOs are successful

                                                titanus@asrock:~$ telnet 46.21.105.38 25
                                                Trying 46.21.105.38...
                                                Connected to 46.21.105.38.
                                                Escape character is '^]'.
                                                220 aptget.aptget.dk ESMTP Postfix
                                                EHLO Hej
                                                250-aptget.aptget.dk
                                                250-PIPELINING
                                                250-SIZE 26214400
                                                250-ETRN
                                                250-STARTTLS
                                                250-AUTH PLAIN LOGIN
                                                250-AUTH=PLAIN LOGIN
                                                250-ENHANCEDSTATUSCODES
                                                250-8BITMIME
                                                250 DSN
                                                MAIL FROM:<>
                                                250 2.1.0 Ok
                                                RCPT TO:<real-user@...>
                                                250 2.1.5 Ok
                                                RCPT TO:<non-existent@...>
                                                250 2.1.5 Ok
                                                QUIT
                                                221 2.0.0 Bye
                                                Connection closed by foreign host.

                                                If non-existent@... is substituted with non-existent@...,
                                                then it is still rejected with "... unknown in virtual mailbox table".

                                                When trying with submission through telnet, I'm afraid I can't get the
                                                syntax right. But when using the mail client Claws Mail, Postfix
                                                accepts non-existent addresses for cogky.dk

                                                ...
                                                [17:51:52] ESMTP< 235 2.7.0 Authentication successful
                                                [17:51:52] ESMTP> MAIL FROM:<nicky@...> SIZE=371
                                                [17:51:52] SMTP< 250 2.1.0 Ok
                                                [17:51:52] SMTP> RCPT TO:<non-existent@...>
                                                [17:51:52] SMTP< 250 2.1.5 Ok
                                                ...

                                                Thank you, Titanus
                                              • Wietse Venema
                                                ... You appear to have a wild-card rule that replaces @cogky.dk with @aptget.dk. Such a rule matches all addresses including invalid ones. Instead use a MySQL
                                                Message 23 of 28 , Mar 25, 2013
                                                  Titanus Eramius:
                                                  > > OK, the table is working as it should. Now let's find out
                                                  > > why the bogus recipient is accepted:
                                                  > >
                                                  > > Next step:
                                                  > >
                                                  > > - Connect to the public (not content re-injection) SMTP port and try
                                                  ...
                                                  > MAIL FROM:<>
                                                  > 250 2.1.0 Ok
                                                  > RCPT TO:<real-user@...>
                                                  > 250 2.1.5 Ok
                                                  > RCPT TO:<non-existent@...>
                                                  > 250 2.1.5 Ok

                                                  > If non-existent@... is substituted with non-existent@...,
                                                  > then it is still rejected with "... unknown in virtual mailbox table".

                                                  You appear to have a wild-card rule that replaces @... with
                                                  @.... Such a rule matches all addresses including invalid ones.

                                                  Instead use a MySQL query as decribed in
                                                  http://tech.groups.yahoo.com/group/postfix-users/message/247913

                                                  Wietse
                                                • Titanus Eramius
                                                  Mon, 25 Mar 2013 14:09:04 -0400 (EDT) skrev Wietse Venema ... Thank you for the link, it was very informative, but didn t solve the problem. I also tried
                                                  Message 24 of 28 , Apr 5, 2013
                                                    Mon, 25 Mar 2013 14:09:04 -0400 (EDT) skrev Wietse Venema
                                                    <wietse@...>:

                                                    > Titanus Eramius:

                                                    > > MAIL FROM:<>
                                                    > > 250 2.1.0 Ok
                                                    > > RCPT TO:<real-user@...>
                                                    > > 250 2.1.5 Ok
                                                    > > RCPT TO:<non-existent@...>
                                                    > > 250 2.1.5 Ok
                                                    >
                                                    > > If non-existent@... is substituted with non-existent@...,
                                                    > > then it is still rejected with "... unknown in virtual mailbox
                                                    > > table".
                                                    >
                                                    > You appear to have a wild-card rule that replaces @... with
                                                    > @.... Such a rule matches all addresses including invalid ones.
                                                    >
                                                    > Instead use a MySQL query as decribed in
                                                    > http://tech.groups.yahoo.com/group/postfix-users/message/247913
                                                    >
                                                    > Wietse

                                                    Thank you for the link, it was very informative, but didn't solve the
                                                    problem. I also tried making a virtual_mailbox_maps MySQL query that
                                                    always returned false, but Postfix still accepted all mail, and then
                                                    bounced it after Dovecot rejected it.

                                                    I have converted virtual_mailbox_maps and virtual_mailbox_domains to
                                                    textfiles, so it should be easier to debug on the setup. Please note
                                                    that I had to change server to experiment like this, since I depend
                                                    on the other server.

                                                    The servername is nt-data.dk, and the hosted domain (which all mail is
                                                    accepted for) is nt-backup.dk. The behavior is the same, so mail sent
                                                    to non_existent@... is rejected, while mail sent to
                                                    non_existent@... is accepted, and then bounced.

                                                    In main.cf (please see the bottom for postconf -n) is
                                                    virtual_mailbox_domains =
                                                    hash:/etc/postfix/virtual_mailbox_domains.cf
                                                    virtual_mailbox_maps =
                                                    hash:/etc/postfix/virtual_mailbox_maps.cf

                                                    And the content of those files is
                                                    virtual_mailbox_domains.cf:
                                                    nt-backup.dk OK
                                                    nt-data.dk OK

                                                    virtual_mailbox_maps.cf:
                                                    test@... OK
                                                    info@... OK

                                                    It all works like a charm, besides the point that Postfix accepts
                                                    mail to non-existent users on the hosted domain.

                                                    In addition I have read through the relevant documentation again, but I
                                                    still can't figure out where or what the problem might be.

                                                    Thanks again


                                                    postconf -n
                                                    alias_maps = hash:/etc/aliases

                                                    bounce_template_file = /etc/postfix/bounce.cf

                                                    broken_sasl_auth_clients = yes

                                                    config_directory = /etc/postfix

                                                    delay_warning_time = 4

                                                    disable_vrfy_command = yes

                                                    inet_interfaces = all

                                                    local_recipient_maps = $virtual_mailbox_maps

                                                    maximal_queue_lifetime = 15

                                                    mydestination =

                                                    myhostname = ntdata.nt-data.dk

                                                    mynetworks = 127.0.0.0/8

                                                    recipient_canonical_classes = envelope_recipient

                                                    recipient_canonical_maps = hash:/etc/postfix/pfix-no-srs.cf,
                                                    tcp:127.0.0.1:10002

                                                    sender_canonical_classes = envelope_sender

                                                    sender_canonical_maps = hash:/etc/postfix/pfix-no-srs.cf,
                                                    tcp:127.0.0.1:10001

                                                    smtp_tls_security_level = may

                                                    smtp_tls_session_cache_database =
                                                    btree:$data_directory/smtp_tls_session_cache

                                                    smtpd_data_restrictions =
                                                    reject_unauth_pipelining,
                                                    reject_multi_recipient_bounce,
                                                    permit

                                                    smtpd_helo_required = yes

                                                    smtpd_recipient_restrictions =
                                                    reject_non_fqdn_sender,
                                                    reject_non_fqdn_recipient,
                                                    reject_unknown_sender_domain,
                                                    reject_unknown_recipient_domain,
                                                    reject_rbl_client truncate.gbudb.net,
                                                    reject_unauth_destination,
                                                    permit

                                                    smtpd_sasl_auth_enable = yes

                                                    smtpd_sasl_exceptions_networks = $mynetworks

                                                    smtpd_sasl_path = private/auth

                                                    smtpd_sasl_security_options = noanonymous

                                                    smtpd_sasl_type = dovecot

                                                    smtpd_tls_ask_ccert = yes

                                                    smtpd_tls_cert_file = /etc/ssl/self-signed/smtpd.crt

                                                    smtpd_tls_key_file = /etc/ssl/self-signed/smtpd.key

                                                    smtpd_tls_loglevel = 1

                                                    smtpd_tls_received_header = yes

                                                    smtpd_tls_security_level = may

                                                    smtpd_tls_session_cache_database =
                                                    btree:$data_directory/smtpd_tls_session_cache

                                                    tls_random_source = dev:/dev/urandom

                                                    transport_maps = hash:/etc/postfix/transport.cf

                                                    virtual_mailbox_domains = hash:/etc/postfix/virtual_mailbox_domains.cf

                                                    virtual_mailbox_maps = hash:/etc/postfix/virtual_mailbox_maps.cf

                                                    virtual_transport = dovecot
                                                  • Brian Evans
                                                    ... You say you return false ? Postfix expects to receive no results (a.k.a. 0 rows) if a virtual_mailbox_maps address in mysql does not exist. Do not return
                                                    Message 25 of 28 , Apr 5, 2013
                                                      On 4/5/2013 6:56 AM, Titanus Eramius wrote:
                                                      > Mon, 25 Mar 2013 14:09:04 -0400 (EDT) skrev Wietse Venema
                                                      > <wietse@...>:
                                                      >
                                                      >> Titanus Eramius:
                                                      >>> MAIL FROM:<>
                                                      >>> 250 2.1.0 Ok
                                                      >>> RCPT TO:<real-user@...>
                                                      >>> 250 2.1.5 Ok
                                                      >>> RCPT TO:<non-existent@...>
                                                      >>> 250 2.1.5 Ok
                                                      >>> If non-existent@... is substituted with non-existent@...,
                                                      >>> then it is still rejected with "... unknown in virtual mailbox
                                                      >>> table".
                                                      >> You appear to have a wild-card rule that replaces @... with
                                                      >> @.... Such a rule matches all addresses including invalid ones.
                                                      >>
                                                      >> Instead use a MySQL query as decribed in
                                                      >> http://tech.groups.yahoo.com/group/postfix-users/message/247913
                                                      >>
                                                      >> Wietse
                                                      > Thank you for the link, it was very informative, but didn't solve the
                                                      > problem. I also tried making a virtual_mailbox_maps MySQL query that
                                                      > always returned false, but Postfix still accepted all mail, and then
                                                      > bounced it after Dovecot rejected it.

                                                      You say you return "false"?
                                                      Postfix expects to receive no results (a.k.a. 0 rows) if a
                                                      virtual_mailbox_maps address in mysql does not exist.
                                                      Do not return "false", empty string, null, or any other value if it does
                                                      not exist.

                                                      Brian
                                                    • Titanus Eramius
                                                      Fri, 05 Apr 2013 08:49:39 -0400 skrev Brian Evans ... False may be the wrong word, and I m sorry if it is. What I mean is, virtual_mailbox_maps always returns
                                                      Message 26 of 28 , Apr 5, 2013
                                                        Fri, 05 Apr 2013 08:49:39 -0400 skrev Brian Evans
                                                        <grknight@...>:

                                                        > > Thank you for the link, it was very informative, but didn't solve
                                                        > > the problem. I also tried making a virtual_mailbox_maps MySQL query
                                                        > > that always returned false, but Postfix still accepted all mail,
                                                        > > and then bounced it after Dovecot rejected it.
                                                        >
                                                        > You say you return "false"?
                                                        > Postfix expects to receive no results (a.k.a. 0 rows) if a
                                                        > virtual_mailbox_maps address in mysql does not exist.
                                                        > Do not return "false", empty string, null, or any other value if it
                                                        > does not exist.

                                                        False may be the wrong word, and I'm sorry if it is. What I mean is,
                                                        virtual_mailbox_maps always returns nothing from MySQL, like so:

                                                        titanus@ntdata:/etc/postfix$ sudo postmap -q test@...
                                                        mysql:/etc/postfix/mysql_virtual_mailbox_maps.cf
                                                        titanus@ntdata:/etc/postfix$ echo $?
                                                        1
                                                        (this user exists)

                                                        titanus@ntdata:/etc/postfix$ sudo postmap -q non_existent@...
                                                        mysql:/etc/postfix/mysql_virtual_mailbox_maps.cf
                                                        titanus@ntdata:/etc/postfix$ echo $?
                                                        1
                                                        (this user does not)

                                                        I did this because I had some trouble constructing the query-string
                                                        Wietse recommended, and thought this would be a simple and easy way to
                                                        test if virtual_mailbox_maps was the problem.

                                                        When trying the syntax within the MySQL CLI, a "Empty set" is returned
                                                        when querying for a non-existent user

                                                        mysql> SELECT username FROM mailbox
                                                        -> WHERE username = 'non_existent@...';
                                                        Empty set (0.00 sec)


                                                        I hope this better explains what I meant
                                                        Cheers
                                                      • Titanus Eramius
                                                        Solved it :-) When sending to unknown users, Postfix now rejects the mail with User unknown in virtual mailbox table , and it does so for hosted (that is,
                                                        Message 27 of 28 , Apr 6, 2013
                                                          Solved it :-)

                                                          When sending to unknown users, Postfix now rejects the mail with "User
                                                          unknown in virtual mailbox table", and it does so for hosted (that is,
                                                          virtual mailbox domains) domains as well.

                                                          It seems the SRS-daemon* I have been using with the main.cf parameters
                                                          recipient_canonical_maps
                                                          recipient_canonical_classes
                                                          sender_canonical_maps
                                                          sender_canonical_classes

                                                          was the root of the problem. I have just commented them out to solve
                                                          it. Reading through the documentation for those four parameters, does
                                                          not seem to indicate why they would mess with Postfix' ability to use
                                                          virtual_mailbox_maps.

                                                          But I guess my lack of understanding about Postfix internals is a
                                                          problem as well. I am sorry for the wasted time, and would like to
                                                          thank all who helped out.

                                                          Have a nice weekend


                                                          * https://github.com/Fruneau/pfixtools
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