illumos: manual page: sendmail.5

SENDMAIL(5) File Formats and Configurations SENDMAIL(5)

NAME

sendmail, sendmail.cf, submit.cf - sendmail configuration files

SYNOPSIS

/etc/mail/sendmail.cf

/etc/mail/submit.cf

DESCRIPTION

The sendmail.cf and submit.cf files are the configuration files for
sendmail(8). Starting with version 8.12 of sendmail, which was shipped
with version 9 of the Solaris operating system, two configuration files
are used for submission and transmission of mail, instead of only
sendmail.cf, as before. These are:

sendmail.cf
Remains the principal sendmail configuration file. Used
for the Mail Transmission Agent (MTA).

submit.cf
Used for the Mail Submission Program (MSP). The MSP is
used to submit mail messages. Unlike the MTA, it does not
run as an SMTP daemon.

The MSP does not require root privileges, thus the two-file model
provides better security than the pre-sendmail 8.12 model, in which the
MSP ran as a daemon and required root privileges.

In the default sendmail configuration, sendmail uses submit.cf, as
indicated in ps(1) output. In ps output, you will observe two sendmail
invocations, such as the ones below:

/usr/lib/sendmail -Ac -q15m
/usr/lib/sendmail -bd -q15m

The first indicates the use of submit.cf, with the client queue
(/var/spool/clientmqueue) being checked--and, if needed, flushed--every
15 minutes. The second invocation runs sendmail as a daemon, waiting for
incoming SMTP connections.

As shipped, sendmail.cf and, in particular, submit.cf, are appropriate
for most environments. Where a knowledgeable system administrator needs
to make a change, he should use the following procedures.

For sendmail.cf:

1. Change directories to the directory that contains the source
files for the configuration files.

# cd /etc/mail/cf/cf

2. Create a copy of the sendmail file for your system.

# cp sendmail.mc `hostname`.mc

3. Edit `hostname`.mc. Make changes suitable for your system and
environment.

4. Run make to generate the configuration file.

# /usr/bin/make `hostname`.cf

5. Copy the newly generated file to its correct location.

# cp `hostname`.cf /etc/mail/sendmail.cf

6. Restart the sendmail service.

# svcadm restart sendmail

You must restart sendmail for sendmail.cf file changes to take effect, as
indicated in step 6. Steps 4 - 6 can be automated. See Automated
Rebuilding of Configuration Files below.

For submit.cf:

1. Change directories to the directory that contains the source
files for the configuration files.

# cd /etc/mail/cf/cf

2. Create a copy of the submit file for your system.

# cp submit.mc submit-`hostname`.mc

3. Edit submit-`hostname`.mc. Make changes suitable for your
system and environment.

4. Run make to generate the configuration file.

# /usr/bin/make submit-`hostname`.cf

5. Copy the newly generated file to its correct location.

# cp submit-`hostname`.cf /etc/mail/submit.cf

You do not need to restart sendmail for changes to submit.cf to take
effect. Steps 4 and 5 can be automated. See Automated Rebuilding of
Configuration Files below.

Enabling Access to Remote Clients

The sendmail(8) man page describes how the config/local_only property can
be set to true or false to disallow or allow, respectively, access to
remote clients for unmodified systems.

Setting values for the following properties for the service instance
svc:/network/smtp:sendmail results in automated (re)building of
configuration files:

path_to_sendmail_mc
path_to_submit_mc

The values for these properties should be strings which represent the
path name of the .mc files referred to in steps 2 and 3 of both
procedures above. Recommended values are:

/etc/mail/cf/cf/`hostname`.mc
/etc/mail/cf/cf/submit-`hostname`.mc

Each property, if set, results in the corresponding .mc file being used
to (re)build the matching .cf file when the service is started.

These properties persist across updates. To prevent an update from
clobbering your .cf file, or renaming it to .cf.old, you can set the
desired properties instead.

FILES

/etc/mail/cf/README
Describes sendmail configuration files.