    DNSBLOG(8)                                                          DNSBLOG(8)

    NAME
           dnsblog - Postfix DNS white/blacklist logger

    SYNOPSIS
           dnsblog [generic Postfix daemon options]

    DESCRIPTION
           The  dnsblog(8)  server implements an ad-hoc DNS white/blacklist lookup
           service. This may eventually be replaced by an UDP client that is built
           directly into the postscreen(8) server.

    PROTOCOL
           With each connection, the dnsblog(8) server receives a DNS white/black-
           list domain name, an IP address, and an  ID.   If  the  IP  address  is
           listed  under  the  DNS white/blacklist, the dnsblog(8) server logs the
           match and replies with the query arguments plus an  address  list  with
           the resulting IP addresses, separated by whitespace, and the reply TTL.
           Otherwise it replies with the query arguments  plus  an  empty  address
           list  and  the  reply TTL (-1 if unavailable).  Finally, The dnsblog(8)
           server closes the connection.

    DIAGNOSTICS
           Problems and transactions are logged to syslogd(8).

    CONFIGURATION PARAMETERS
           Changes to main.cf are picked up automatically, as dnsblog(8) processes
           run for only a limited amount of time. Use the command "postfix reload"
           to speed up a change.

           The text below provides only a parameter summary. See  postconf(5)  for
           more details including examples.

           config_directory (see 'postconf -d' output)
                  The  default  location of the Postfix main.cf and master.cf con-
                  figuration files.

           daemon_timeout (18000s)
                  How much time a Postfix daemon process  may  take  to  handle  a
                  request before it is terminated by a built-in watchdog timer.

           postscreen_dnsbl_sites (empty)
                  Optional list of DNS white/blacklist domains, filters and weight
                  factors.

           ipc_timeout (3600s)
                  The time limit for sending  or  receiving  information  over  an
                  internal communication channel.

           process_id (read-only)
                  The process ID of a Postfix command or daemon process.

           process_name (read-only)
                  The process name of a Postfix command or daemon process.

           queue_directory (see 'postconf -d' output)
                  The location of the Postfix top-level queue directory.

           syslog_facility (mail)
                  The syslog facility of Postfix logging.

           syslog_name (see 'postconf -d' output)
                  The  mail  system  name that is prepended to the process name in
                  syslog records, so that "smtpd"  becomes,  for  example,  "post-
                  fix/smtpd".

    SEE ALSO
           smtpd(8), Postfix SMTP server
           postconf(5), configuration parameters
           syslogd(5), system logging

    LICENSE
           The Secure Mailer license must be distributed with this software.

    HISTORY
           This service was introduced with Postfix version 2.8.

    AUTHOR(S)
           Wietse Venema
           IBM T.J. Watson Research
           P.O. Box 704
           Yorktown Heights, NY 10598, USA

           Wietse Venema
           Google, Inc.
           111 8th Avenue
           New York, NY 10011, USA

                                                                        DNSBLOG(8)