'\" te

.\" Copyright (c) 1998-2003 Sendmail, Inc. and its suppliers. All rights reserved.

.\" Copyright (c) 1983, 1997 Eric P. Allman. All rights reserved.

.\" Copyright (c) 1988, 1991, 1993 The Regents of the University of California. All rights reserved.

.\" Portions Copyright (c) 1998, 2016, Oracle and/or its affiliates. All rights reserved.

.SH NAME

sendmail \- send mail over the internet

.SH SYNOPSIS

.LP

.nf

\fB/usr/lib/sendmail\fR [\fB-Ac\fR] [\fB-Am\fR] [\fB-ba\fR] [\fB-bD\fR] [\fB-bd\fR] [\fB-bi\fR] [\fB-bl\fR] 

     [\fB-bm\fR] [\fB-bp\fR] [\fB-bP\fR] [\fB-bs\fR] [\fB-bt\fR] [\fB-bv\fR] [\fB-B\fR \fItype\fR] [\fB-C\fR \fIfile\fR]

     [\fB-D\fR \fIlogfile\fR] [\fB-d\fR \fIX\fR] [\fB-F\fR \fIfullname\fR] [\fB-f\fR \fIname\fR] [\fB-G\fR] 

     [\fB-h\fR \fIN\fR] [\fB-L \fItag\fR\fR] [\fB-M\fR x\fIvalue\fR] [\fB-N\fR \fInotifications\fR] [\fB-n\fR] 

     [\fB-O\fR\fIoption\fR =\fIvalue\fR] [\fB-o\fR x\fIvalue\fR] [\fB-p\fR \fIprotocol\fR] 

     [\fB-Q\fR [\fIreason\fR]] [\fB-q\fR [\fItime\fR]] [\fB-q\fR \fIXstring\fR] [\fB-R\fR \fIret\fR] 

     [\fB-r\fR \fIname\fR] [\fB-t\fR] [\fB-V\fR \fIenvid\fR] [\fB-v\fR] [\fB-X\fR \fIlogfile\fR] 

     [\fIaddress\fR]...

.fi

.SH DESCRIPTION

.sp

.LP

The \fBsendmail\fR utility sends a message to one or more people, routing the message over whatever networks are necessary. \fBsendmail\fR does internetwork forwarding as necessary to deliver the message to the correct place.

.sp

.LP

\fBsendmail\fR is not intended as a user interface routine. Other programs provide user-friendly front ends. \fBsendmail\fR is used only to deliver pre-formatted messages.

.sp

.LP

With no flags, \fBsendmail\fR reads its standard input up to an EOF, or a line with a single dot, and sends a copy of the letter found there to all of the addresses listed. It determines the network to use based on the syntax and contents of the addresses.

.sp

.LP

Local addresses are looked up in the local \fBaliases\fR(5) file, or in a name service as defined by the \fBnsswitch.conf\fR(5) file, and aliased appropriately. In addition, if there is a \fB.forward\fR file in a recipient's home directory, \fBsendmail\fR forwards a copy of each message to the list of recipients that file contains. Refer to the \fBNOTES\fR section for more information about \fB.forward\fR files. Aliasing can be prevented by preceding the address with a backslash. 

.sp

.LP

There are several conditions under which the expected behavior is for the alias database to be either built or rebuilt. This cannot occur under any circumstances unless root owns \fBand\fR has exclusive write permission to the \fB/etc/mail/aliases*\fR files.

.sp

.LP

If a message is found to be undeliverable, it is returned to the sender with diagnostics that indicate the location and nature of the failure; or, the message is placed in a \fBdead.letter\fR file in the sender's home directory.

.SS "Service Management"

.sp

.LP

The \fBsendmail\fR service is managed by the service management facility, \fBsmf\fR(7), under the service identifiers:

.sp

.in +2

.nf

svc:/network/smtp:sendmail

svc:/network/sendmail-client:default

.fi

.in -2

.sp

.sp

.LP

Administrative actions on these services, such as enabling, disabling, or requesting restart, can be performed using \fBsvcadm\fR(8). The services' status can be queried using the \fBsvcs\fR(1) command.

.sp

.LP

These are separate services rather than instances of the same service so that other services can properly express any dependencies. In particular, here are some guidelines about which service/instance should be depended on for which purposes:

.RS +4

.TP

.ie t \(bu

.el o

For a service that uses \fBsendmail\fR to send mail, an optional dependency on the service \fBsvc:/network/sendmail-client\fR might be in order. 

.RE

.RS +4

.TP

.ie t \(bu

.el o

For a service that needs to receive mail in general, but does not depend on \fBsendmail\fR being the particular SMTP receiver, a dependency on the service \fBsvc:/network/smtp\fR might be in order. 

.RE

.RS +4

.TP

.ie t \(bu

.el o

For a service that needs to interact with sendmail in particular, such as a \fBMilter\fR, a dependency on the instance \fBsvc:/network/smtp:sendmail\fR might be in order. 

.RE

.sp

.LP

For the last two, note the difference, as the latter has the \fB":sendmail"\fR instance specification, whereas the former does not, thus representing the more general service.

.SS "Enabling Access to Remote Clients"

.sp

.LP

On an unmodified system, access to \fBsendmail\fR by remote clients is enabled and disabled through the service management facility (see \fBsmf\fR(7)). In particular, remote access is determined by the value of the \fBlocal_only\fR SMF property:

.sp

.in +2

.nf

svc:/network/smtp:sendmail/config/local_only = true

.fi

.in -2

.sp

.sp

.LP

A setting of \fBtrue\fR, as above, disallows remote access; \fBfalse\fR allows remote access. The default value is \fBtrue\fR.

.sp

.LP

The following example shows the sequence of SMF commands used to enable \fBsendmail\fR to allow access to remote systems:

.sp

.in +2

.nf

# \fBsvccfg -s svc:/network/smtp:sendmail setprop config/local_only = false\fR

# \fBsvcadm refresh svc:/network/smtp:sendmail\fR

# \fBsvcadm restart svc:/network/smtp:sendmail\fR

.fi

.in -2

.sp

.sp

.LP

See \fBsvcadm\fR(8) and \fBsvccfg\fR(8).

.sp

.LP

Note, however, on a system where any of the \fBsendmail\fR(5) files have been customized, setting this property might not have the intended effect. See \fBsendmail\fR(5) for details.

.SS "Automated Rebuilding of Configuration Files"

.sp

.LP

See \fBsendmail\fR(5) for details on which service properties can be set to automate (re)building of configuration files when the service is started.

.SS "Restricting Host Access"

.sp

.LP

\fBsendmail\fR uses TCP Wrappers to restrict access to hosts. It uses the service name of \fBsendmail\fR for \fBhosts_access()\fR. For more information on TCP Wrappers, see \fBtcpd\fR(8) and \fBhosts_access\fR(5) in the \fBsecurity/tcp-wrapper\fR package. \fBtcpd\fR(8) and \fBhosts_access\fR(5) are not part of the Solaris man pages.

.SS "Startup Options"

.sp

.LP

The \fB/etc/default/sendmail\fR file stores startup options for \fBsendmail\fR so that the options are not removed when a host is upgraded. See also \fBsendmail\fR(5) for details on which service properties can be set to automate (re)building of configuration files when the service is started.

.sp

.LP

You can use the following variables in the \fB/etc/default/sendmail\fR startup file:

.sp

.ne 2

.mk

.na

\fBCLIENTOPTIONS=\fIstring\fR\fR

.ad

.br

.sp .6

.RS 4n

Selects additional options to be used with the client daemon, which looks in the client-only queue (\fB/var/spool/clientmqueue\fR) and acts as a client queue runner. No syntax checking is done, so be careful when making changes to this variable.

.RE

.sp

.ne 2

.mk

.na

\fBCLIENTQUEUEINTERVAL=\fI#\fR\fR

.ad

.br

.sp .6

.RS 4n

Similar to the \fBQUEUEINTERVAL\fR option, \fBCLIENTQUEUEINTERVAL\fR sets the time interval for mail queue runs. However, the \fBCLIENTQUEUEINTERVAL\fR option controls the functions of the client daemon, instead of the functions of the master daemon. Typically, the master daemon is able to deliver all messages to the SMTP port. However, if the message load is too high or the master daemon is not running, then messages go into the client-only queue, \fB/var/spool/clientmqueue\fR. The client daemon, which checks in the client-only queue, then acts as a client queue processor.

.RE

.sp

.ne 2

.mk

.na

\fBETRN_HOSTS=\fIstring\fR\fR

.ad

.br

.sp .6

.RS 4n

Enables an SMTP client and server to interact immediately without waiting for the queue run intervals, which are periodic. The server can immediately deliver the portion of its queue that goes to the specified hosts. For more information, refer to the \fBetrn\fR(8) man page.

.RE

.sp

.ne 2

.mk

.na

\fBMODE=-bd\fR

.ad

.br

.sp .6

.RS 4n

Selects the mode to start \fBsendmail\fR with. Use the \fB-bd\fR option or leave it undefined.

.RE

.sp

.ne 2

.mk

.na

\fBOPTIONS=\fIstring\fR\fR

.ad

.br

.sp .6

.RS 4n

Selects additional options to be used with the master daemon. No syntax checking is done, so be careful when making changes to this variable.

.RE

.sp

.ne 2

.mk

.na

\fBQUEUEINTERVAL=\fI#\fR\fR

.ad

.br

.sp .6

.RS 4n

Sets the interval for mail queue runs on the master daemon. \fI#\fR can be a positive integer that is followed by either \fBs\fR for seconds, \fBm\fR for minutes, \fBh\fR for hours, \fBd\fR for days, or \fBw\fR for weeks. The syntax is checked before \fBsendmail\fR is started. If the interval is negative or if the entry does not end with an appropriate letter, the interval is ignored and \fBsendmail\fR starts with a queue interval of 15 minutes.

.RE

.sp

.ne 2

.mk

.na

\fBQUEUEOPTIONS=p\fR

.ad

.br

.sp .6

.RS 4n

Enables one persistent queue runner that sleeps between queue run intervals, instead of a new queue runner for each queue run interval. You can set this option to \fBp\fR, which is the only setting available. Otherwise, this option is not set.

.RE

.SS "Mail Filter API"

.sp

.LP

\fBsendmail\fR supports a mail filter API called "milter". For more information, see \fB/usr/include/libmilter/README\fR and http://www.milter.org

.SH OPTIONS

.sp

.LP

The following options are supported:

.sp

.ne 2

.mk

.na

\fB\fB-Ac\fR\fR

.ad

.br

.sp .6

.RS 4n

Uses \fBsubmit.cf\fR even if the operation mode does not indicate an initial mail submission.

.RE

.sp

.ne 2

.mk

.na

\fB\fB-Am\fR\fR

.ad

.br

.sp .6

.RS 4n

Uses \fBsendmail.cf\fR even if the operation mode indicates an initial mail submission.

.RE

.sp

.ne 2

.mk

.na

\fB\fB-ba\fR\fR

.ad

.br

.sp .6

.RS 4n

Goes into \fBARPANET\fR mode. All input lines must end with a \fBRETURN-LINEFEED\fR, and all messages are generated with a \fBRETURN-LINEFEED\fR at the end. Also, the \fBFrom:\fR and \fBSender:\fR fields are examined for the name of the sender.

.RE

.sp

.ne 2

.mk

.na

\fB\fB-bc\fR\fR

.ad

.br

.sp .6

.RS 4n

Check the configuration file.

.RE

.sp

.ne 2

.mk

.na

\fB\fB-bd\fR\fR

.ad

.br

.sp .6

.RS 4n

Runs as a daemon in the background, waiting for incoming SMTP connections.

.RE

.sp

.ne 2

.mk

.na

\fB\fB-bD\fR\fR

.ad

.br

.sp .6

.RS 4n

Runs as a daemon in the foreground, waiting for incoming SMTP connections.

.RE

.sp

.ne 2

.mk

.na

\fB\fB-bi\fR\fR

.ad

.br

.sp .6

.RS 4n

Initializes the \fBaliases\fR(5) database. Root must own \fIand\fR have exclusive write permission to the \fB/etc/mail/aliases*\fR files for successful use of this option.

.RE

.sp

.ne 2

.mk

.na

\fB\fB-bl\fR\fR

.ad

.br

.sp .6

.RS 4n

Runs as a daemon (like \fB-bd\fR) but accepts only loopback SMTP connections.

.RE

.sp

.ne 2

.mk

.na

\fB\fB-bm\fR\fR

.ad

.br

.sp .6

.RS 4n

Delivers mail in the usual way (default).

.RE

.sp

.ne 2

.mk

.na

\fB\fB-bp\fR\fR

.ad

.br

.sp .6

.RS 4n

Prints a summary of the mail queues.

.RE

.sp

.ne 2

.mk

.na

\fB\fB-bP\fR\fR

.ad

.br

.sp .6

.RS 4n

Prints the number of entries in the queues. This option is only available with shared memory support.

.RE

.sp

.ne 2

.mk

.na

\fB\fB-bs\fR\fR

.ad

.br

.sp .6

.RS 4n

Uses the SMTP protocol as described in RFC 2821. This flag implies all the operations of the \fB-ba\fR flag that are compatible with \fBSMTP\fR.

.RE

.sp

.ne 2

.mk

.na

\fB\fB-bt\fR\fR

.ad

.br

.sp .6

.RS 4n

Runs in address test mode. This mode reads addresses and shows the steps in parsing; it is used for debugging configuration tables.

.RE

.sp

.ne 2

.mk

.na

\fB\fB-bv\fR\fR

.ad

.br

.sp .6

.RS 4n

Verifies names only. Does not try to collect or deliver a message. Verify mode is normally used for validating users or mailing lists.

.RE

.sp

.ne 2

.mk

.na

\fB\fB-B\fR \fItype\fR\fR

.ad

.br

.sp .6

.RS 4n

Indicates body \fItype\fR (\fB7BIT\fR or \fB8BITMIME\fR).

.RE

.sp

.ne 2

.mk

.na

\fB\fB-C\fR \fIfile\fR\fR

.ad

.br

.sp .6

.RS 4n

Uses alternate configuration file.

.RE

.sp

.ne 2

.mk

.na

\fB\fB-D\fR \fIlogfile\fR\fR

.ad

.br

.sp .6

.RS 4n

Send debugging output to the indicated log file instead of \fBstdout\fR.

.RE

.sp

.ne 2

.mk

.na

\fB\fB-d\fR \fIX\fR\fR

.ad

.br

.sp .6

.RS 4n

Sets debugging value to \fIX\fR.

.RE

.sp

.ne 2

.mk

.na

\fB\fB-f\fR \fIname\fR\fR

.ad

.br

.sp .6

.RS 4n

Sets the name of the "from" person (that is, the sender of the mail).

.RE

.sp

.ne 2

.mk

.na

\fB\fB-F\fR \fIfullname\fR\fR

.ad

.br

.sp .6

.RS 4n

Sets the full name of the sender.

.RE

.sp

.ne 2

.mk

.na

\fB\fB-G\fR\fR

.ad

.br

.sp .6

.RS 4n

When accepting messages by way of the command line, indicates that they are for relay (gateway) submission. When this flag is set, \fBsendmail\fR might complain about syntactically invalid messages, for example, unqualified host names, rather than fixing them. \fBsendmail\fR does not do any canonicalization in this mode.

.RE

.sp

.ne 2

.mk

.na

\fB\fB-h\fR \fIN\fR\fR

.ad

.br

.sp .6

.RS 4n

Sets the hop count to \fIN\fR. The hop count is incremented every time the mail is processed. When it reaches a limit, the mail is returned with an error message, the victim of an aliasing loop.

.RE

.sp

.ne 2

.mk

.na

\fB\fB-L\fR \fItag\fR\fR

.ad

.br

.sp .6

.RS 4n

Sets the identifier used in \fBsyslog\fR messages to the supplied \fItag\fR.

.RE

.sp

.ne 2

.mk

.na

\fB\fB-M\fR\fIxvalue\fR\fR

.ad

.br

.sp .6

.RS 4n

Sets macro \fIx\fR to the specified \fIvalue\fR.

.RE

.sp

.ne 2

.mk

.na

\fB\fB-n\fR\fR

.ad