Provided by: opensmtpd_6.8.0p2-4build2_amd64
smtpd — Simple Mail Transfer Protocol daemon
smtpd [-dFhnv] [-D macro=value] [-f file] [-P system] [-T trace]
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.
/etc/mailname Alternate server name to use. /etc/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.
forward(5), smtpd.conf(5), mailwrapper(8), smtpctl(8)
J. Klensin, Simple Mail Transfer Protocol, RFC 5321, October 2008.
The smtpd program first appeared in OpenBSD 4.6.