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/blacklist 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 configuration 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, "postfix/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(8postfix)