smtpd(8) — Linux manual page

NAME | SYNOPSIS | DESCRIPTION | FILES | SEE ALSO | STANDARDS | HISTORY | COLOPHON

SMTPD(8)               BSD System Manager's Manual              SMTPD(8)

NAME         top

     smtpd — Simple Mail Transfer Protocol daemon

SYNOPSIS         top

     smtpd [-dFhnv] [-D macro=value] [-f file] [-P system] [-T trace]

DESCRIPTION         top

     smtpd is a Simple Mail Transfer Protocol (SMTP) daemon which can be
     used as a machine's primary mail system.  smtpd can listen on a
     network interface and handle SMTP transactions; it can also be fed
     messages through the standard sendmail(8) interface.  It can relay
     messages through remote mail transfer agents or store them locally
     using either the mbox or maildir format.  This implementation
     supports SMTP as defined by RFC 5321 as well as several extensions.
     A running smtpd can be controlled through smtpctl(8).

     The options are as follows:

     -D macro=value
             Define macro to be set to value on the command line.
             Overrides the definition of macro in the configuration
             file.

     -d      Do not daemonize.  If this option is specified, smtpd will
             run in the foreground and log to stderr.

     -F      Do not daemonize.  If this option is specified, smtpd will
             run in the foreground and log to syslogd(8).

     -f file
             Specify an alternative configuration file.

     -h      Display version and usage.

     -n      Configtest mode.  Only check the configuration file for
             validity.

     -P system
             Pause a specific subsystem at startup.  Normal operation
             can be resumed using smtpctl(8).  This option can be used
             multiple times.  The accepted values are:

             mda      Do not schedule local deliveries.
             mta      Do not schedule remote transfers.
             smtp     Do not listen on SMTP sockets.

     -T trace
             Enables real-time tracing at startup.  Normal operation can
             be resumed using smtpctl(8).  This option can be used
             multiple times.  The accepted values are:

             imsg
             io
             smtp (incoming sessions)
             filters
             transfer (outgoing sessions)
             bounce
             scheduler
             expand (aliases/virtual/forward expansion)
             lookup (user/credentials lookups)
             stat
             rules (matched by incoming sessions)
             mproc
             all

     -v      Produce more verbose output.

FILES         top

     /etc/mail/mailname       Alternate server name to use.
     /etc/mail/smtpd.conf     Default smtpd configuration file.
     /var/run/smtpd.sock      UNIX-domain socket used for communication
                              with smtpctl(8).
     /var/spool/smtpd/        Spool directories for mail during
                              processing.
     ~/.forward               User email forwarding information.

SEE ALSO         top

     forward(5), smtpd.conf(5), mailwrapper(8), smtpctl(8)

STANDARDS         top

     J. Klensin, Simple Mail Transfer Protocol, RFC 5321, October 2008.

HISTORY         top

     The smtpd program first appeared in OpenBSD 4.6.

COLOPHON         top

     This page is part of the OpenSMTPD (a FREE implementation of the
     server-side SMTP protocol) project.  Information about the project
     can be found at https://www.opensmtpd.org/.  If you have a bug
     report for this manual page, see
     ⟨https://github.com/OpenSMTPD/OpenSMTPD/issues⟩.  This page was
     obtained from the project's upstream Git repository
     ⟨https://github.com/OpenSMTPD/OpenSMTPD.git⟩ on 2022-12-17.  (At
     that time, the date of the most recent commit that was found in the
     repository was 2022-09-30.)  If you discover any rendering problems
     in this HTML version of the page, or you believe there is a better
     or more up-to-date source for the page, or you have corrections or
     improvements to the information in this COLOPHON (which is not part
     of the original manual page), send a mail to man-pages@man7.org

BSD                          January 3, 2017                         BSD