sendmail - Postfix to Sendmail compatibility interface
sendmail [option ...] [recipient ...]
mailq sendmail -bp
newaliases sendmail -I
The Postfix sendmail(1) command implements the Postfix to Sendmail compatibility interface. For the sake of compatibility with existing applications, some Sendmail command-line options are recognized but silently ignored.
By default, Postfix sendmail(1) reads a message from standard input until EOF or until it reads a line with only a . character, and arranges for delivery. Postfix sendmail(1) relies on the postdrop(1) command to create a queue file in the maildrop directory.
Specific command aliases are provided for other common modes of operation:
mailq List the mail queue. Each entry shows the queue file ID, message size, arrival time, sender, and the recipients that still need to be delivered. If mail could not be delivered upon the last attempt, the reason for failure is shown. This mode of operation is implemented by executing the postqueue(1) command. newaliases Initialize the alias database. If no input file is specified (with the -oA option, see below), the program processes the file(s) specified with the alias_database configuration parameter. If no alias database type is specified, the program uses the type specified with the default_database_type configuration parameter. This mode of operation is implemented by running the postalias(1) command.
Note: it may take a minute or so before an alias database update becomes visible. Use the "postfix reload" command to eliminate this delay.
These and other features can be selected by specifying the appropriate combination of command-line options. Some features are controlled by parameters in the main.cf configuration file.
The following options are recognized:
-Am (ignored) -Ac (ignored) Postfix sendmail uses the same configuration file regardless of whether or not a message is an initial submission. -B body_type The message body MIME type: 7BIT or 8BITMIME. -bd Go into daemon mode. This mode of operation is implemented by executing the "postfix start" command. -bh (ignored) -bH (ignored) Postfix has no persistent host status database. -bi Initialize alias database. See the newaliases command above. -bm Read mail from standard input and arrange for delivery. This is the default mode of operation. -bp List the mail queue. See the mailq command above. -bs Stand-alone SMTP server mode. Read SMTP commands from standard input, and write responses to standard output. In stand-alone SMTP server mode, mail relaying and other access controls are disabled by default. To enable them, run the process as the mail_owner user.
This mode of operation is implemented by running the smtpd(8) daemon.
-bv Do not collect or deliver a message. Instead, send an email report after verifying each recipient address. This is useful for testing address rewriting and routing configurations.
This feature is available in Postfix version 2.1 and later.
-C config_file -C config_dir The path name of the Postfix main.cf file, or of its parent directory. This information is ignored with Postfix versions before 2.3.
With all Postfix versions, you can specify a directory pathname with the MAIL_CONFIG environment variable to override the location of configuration files.
-F Set the sender full name. This is used only with messages that have no From: message header. -f sender Set the envelope sender address. This is the address where delivery problems are sent to. With Postfix versions before 2.1, the Errors-To: message header overrides the error return address. -G Gateway (relay) submission, as opposed to initial user submission. Either do not rewrite addresses at all, or update incomplete addresses with the domain information specified with remote_header_rewrite_domain.
This option is ignored before Postfix version 2.3.
-h hop_count (ignored) Hop count limit. Use the hopcount_limit configuration parameter instead. -I Initialize alias database. See the newaliases command above. -i When reading a message from standard input, don't treat a line with only a . character as the end of input. -L label (ignored) The logging label. Use the syslog_name configuration parameter instead. -m (ignored) Backwards compatibility. -N dsn (default: delay, failure) Delivery status notification control. Specify either a comma-separated list with one or more of failure (send notification when delivery fails), delay (send notification when delivery is delayed), or success (send notification when the message is delivered); or specify never (dont send any notifications at all).
This feature is available in Postfix 2.3 and later.
-n (ignored) Backwards compatibility. -oAalias_database Non-default alias database. Specify pathname or type:pathname. See postalias(1) for details. -O option=value (ignored) Backwards compatibility. -o7 (ignored) -o8 (ignored) To send 8-bit or binary content, use an appropriate MIME encapsulation and specify the appropriate -B command-line option. -oi When reading a message from standard input, don't treat a line with only a . character as the end of input. -om (ignored) The sender is never eliminated from alias etc. expansions. -o x value (ignored) Set option x to value. Use the equivalent configuration parameter in main.cf instead. -r sender Set the envelope sender address. This is the address where delivery problems are sent to. With Postfix versions before 2.1, the Errors-To: message header overrides the error return address. -R return_limit (ignored) Limit the size of bounced mail. Use the bounce_size_limit configuration parameter instead. -q Attempt to deliver all queued mail. This is implemented by executing the postqueue(1) command.
Warning: flushing undeliverable mail frequently will result in poor delivery performance of all other mail.
-qinterval (ignored) The interval between queue runs. Use the queue_run_delay configuration parameter instead. -qRsite Schedule immediate delivery of all mail that is queued for the named site. This option accepts only site names that are eligible for the "fast flush" service, and is implemented by executing the postqueue(1) command. See flush(8) for more information about the "fast flush" service. -qSsite This command is not implemented. Use the slower "sendmail -q" command instead. -t Extract recipients from message headers. These are added to any recipients specified on the command line.
With Postfix versions prior to 2.1, this option requires that no recipient addresses are specified on the command line.
-U (ignored) Initial user submission. -V envid Specify the envelope ID for notification by servers that support DSN.
This feature is available in Postfix 2.3 and later.
-XV (Postfix 2.2 and earlier: -V) Variable Envelope Return Path. Given an envelope sender address of the form owner-listname@origin, each recipient user@domain receives mail with a personalized envelope sender address.
By default, the personalized envelope sender address is owner-listname+user=domain@origin. The default + and = characters are configurable with the default_verp_delimiters configuration parameter.
-XVxy (Postfix 2.2 and earlier: -Vxy) As -XV, but uses x and y as the VERP delimiter characters, instead of the characters specified with the default_verp_delimiters configuration parameter. -v Send an email report of the first delivery attempt (Postfix versions 2.1 and later). Mail delivery always happens in the background. When multiple -v options are given, enable verbose logging for debugging purposes. -X log_file (ignored) Log mailer traffic. Use the debug_peer_list and debug_peer_level configuration parameters instead.
By design, this program is not set-user (or group) id. However, it must handle data from untrusted users or untrusted machines. Thus, the usual precautions need to be taken against malicious inputs.
Problems are logged to syslogd(8) and to the standard error stream.
MAIL_CONFIG Directory with Postfix configuration files. MAIL_VERBOSE Enable verbose logging for debugging purposes. MAIL_DEBUG Enable debugging with an external command, as specified with the debugger_command configuration parameter.
The following main.cf parameters are especially relevant to this program. The text below provides only a parameter summary. See postconf(5) for more details including examples.
The DEBUG_README file gives examples of how to trouble shoot a Postfix system.
debugger_command (empty) The external command to execute when a Postfix daemon program is invoked with the -D option. debug_peer_level (2) The increment in verbose logging level when a remote client or server matches a pattern in the debug_peer_list parameter. debug_peer_list (empty) Optional list of remote client or server hostname or network address patterns that cause the verbose logging level to increase by the amount specified in $debug_peer_level.
Available in Postfix version 2.2 and later:
authorized_flush_users (static:anyone) List of users who are authorized to flush the queue. authorized_mailq_users (static:anyone) List of users who are authorized to view the queue. authorized_submit_users (static:anyone) List of users who are authorized to submit mail with the sendmail(1) command (and with the privileged postdrop(1) helper command).
bounce_size_limit (50000) The maximal amount of original message text that is sent in a non-delivery notification. fork_attempts (5) The maximal number of attempts to fork() a child process. fork_delay (1s) The delay between attempts to fork() a child process. hopcount_limit (50) The maximal number of Received: message headers that is allowed in the primary message headers. queue_run_delay (1000s) The time between deferred queue scans by the queue manager.
The ETRN_README file describes configuration and operation details for the Postfix "fast flush" service.
fast_flush_domains ($relay_domains) Optional list of destinations that are eligible for per-destination logfiles with mail that is queued to those destinations.
The VERP_README file describes configuration and operation details of Postfix support for variable envelope return path addresses.
default_verp_delimiters (+=) The two default VERP delimiter characters. verp_delimiter_filter (-=+) The characters Postfix accepts as VERP delimiter characters on the Postfix sendmail(1) command line and in SMTP commands.
alias_database (see postconf -d output) The alias databases for local(8) delivery that are updated with "newaliases" or with "sendmail -bi". command_directory (see postconf -d output) The location of all postfix administrative commands. config_directory (see postconf -d output) The default location of the Postfix main.cf and master.cf configuration files. daemon_directory (see postconf -d output) The directory with Postfix support programs and daemon programs. default_database_type (see postconf -d output) The default database type for use in newaliases(1), postalias(1) and postmap(1) commands. delay_warning_time (0h) The time after which the sender receives the message headers of mail that is still queued. enable_errors_to (no) Report mail delivery errors to the address specified with the non-standard Errors-To: message header, instead of the envelope sender address (this feature is removed with Postfix version 2.2, is turned off by default with Postfix version 2.1, and is always turned on with older Postfix versions). mail_owner (postfix) The UNIX system account that owns the Postfix queue and most Postfix daemon processes. queue_directory (see postconf -d output) The location of the Postfix top-level queue directory. remote_header_rewrite_domain (empty) Dont rewrite message headers from remote clients at all when this parameter is empty; otherwise, rewrite message headers and append the specified domain name to incomplete addresses. syslog_facility (mail) The syslog facility of Postfix logging. syslog_name (postfix) The mail system name that is prepended to the process name in syslog records, so that "smtpd" becomes, for example, "postfix/smtpd". trigger_timeout (10s) The time limit for sending a trigger to a Postfix daemon (for example, the pickup(8) or qmgr(8) daemon).
/var/spool/postfix, mail queue /etc/postfix, configuration files
pickup(8), mail pickup daemon qmgr(8), queue manager smtpd(8), SMTP server flush(8), fast flush service postsuper(1), queue maintenance postalias(1), create/update/query alias database postdrop(1), mail posting utility postfix(1), mail system control postqueue(1), mail queue control syslogd(8), system logging
Use "postconf readme_directory" or "postconf html_directory" to locate this information. DEBUG_README, Postfix debugging howto ETRN_README, Postfix ETRN howto VERP_README, Postfix VERP howto
The Secure Mailer license must be distributed with this software.
Wietse Venema IBM T.J. Watson Research P.O. Box 704 Yorktown Heights, NY 10598, USA