Red Hat ENTERPRISE LINUX 5 - DEPLOYMENT Deployment Manual page 408

Chapter 24. Email
• access — Specifies which systems can use Sendmail for outbound email.
• domaintable — Specifies domain name mapping.
• local-host-names — Specifies aliases for the host.
• mailertable — Specifies instructions that override routing for particular domains.
• virtusertable — Specifies a domain-specific form of aliasing, allowing multiple virtual domains
to be hosted on one machine.
Several of the configuration files in /etc/mail/, such as access, domaintable, mailertable
and virtusertable, must actually store their information in database files before Sendmail can use
any configuration changes. To include any changes made to these configurations in their database
files, run the following command:
makemap hash /etc/mail/<name> < /etc/mail/<name>
where <name> is replaced with the name of the configuration file to convert.
For example, to have all emails addressed to the example.com domain delivered to
bob@other-example.com
@example.com bob@other-example.com
To finalize the change, the virtusertable.db file must be updated using the following command
as root:
makemap hash /etc/mail/virtusertable < /etc/mail/virtusertable
This creates an updated virtusertable.db file containing the new configuration.
24.3.1.3. Common Sendmail Configuration Changes
When altering the Sendmail configuration file, it is best not to edit an existing file, but to generate an
entirely new /etc/mail/sendmail.cf file.
Caution
Before changing the sendmail.cf file, it is a good idea to create a backup copy.
To add the desired functionality to Sendmail, edit the /etc/mail/sendmail.mc file as the root
user. When finished, use the m4 macro processor to generate a new sendmail.cf by executing the
following command:
m4 /etc/mail/sendmail.mc > /etc/mail/sendmail.cf
By default, the m4 macro processor is installed with Sendmail but is part of the m4 package.
After creating a new /etc/mail/sendmail.cf file, restart Sendmail for the changes to take effect.
The easiest way to do this is to type the following command:
382
, add the following line to the virtusertable file: