Dependencies

Postfix relies on Cyrus SASL to implement SASL (Simple Authentication and Security Layer).

Make sure the following Cyrus SASL components are installed on the system for Postfix to work as expected:

• cyrus-sasl-lib-2.1.x or later

• cyrus-sasl-plain-2.1.x or later

About Postfix

Postfix is the default email server shipped with the Intelligence Center.

If you want to enable email-based Intelligence Center features such as email notifications, first configure Postfix to handle email traffic.

Postfix configuration and setup may vary, depending on the target environment the Intelligence Center is installed on.

The following links point to relevant sections of the official Postfix documentation:

• Postfix documentation overview

• Postfix basic configuration

• Postfix standard configuration

• Postfix main.cf configuration file parameters

the Intelligence Center ships with an example Postfix configuration file you can use as a customizable template: /etc/postfix/main.cf

• The default installation location of the Postfix configuration file is /etc/postfix.

• The Postfix configuration file is main.cf.

Configure Postfix

To configure Postfix as the default email server for the Intelligence Center:

1. Open main.cf in a text editor:

   vi /etc/postfix/main.cf

   Example main.cf file

   myhostname = box11.platform.host.com

   mydomain = platform.host.com

   myorigin = $mydomain

   mydestination =

    

   relayhost = [smtp.email.server.com]:587

   inet_interfaces = loopback-only

    

   smtp_sasl_security_options = noanonymous

   smtp_sasl_auth_enable = yes

   smtp_use_tls = yes

   smtp_sasl_password_maps = hash:/etc/postfix/sasl_passwd

   smtp_tls_policy_maps = hash:/etc/postfix/tls_policy

2. Set the configuration parameters to appropriate values for your system.

   Links in the table below point to further details about the parameters on the Postfix official documentation.

   Parameter	Description	Example
   myhostname	Defines the host name of the Intelligence Center host server where Postfix is installed.	box11.platform.host.com
   mydomain	Defines the internet name of the Intelligence Center host server where Postfix is installed	platform.host.com
   myorigin	Defines the domain name to use as sent-from and send-to address for local email traffic. Automatic email messages generated by system processes such as cronjobs use the myorigin value for this purpose.	$mydomain (domain with multiple machines) $myhostname (domain with one machine)
   mydestination	Defines the list of domains the email server accepts email from.	localhost localhost.$mydomain mail.$mydomain www.$mydomain ftp.$mydomain
   relayhost	Defines the next-hop destination of non-local email. It identifies the next email handler in the chain of email servers handling non-local email traffic. Format: [smtp.domain.name]:port	[ smtp.email.server.com ]:587
   inet_interfaces	Defines the network interface addresses Postfix receives mail on.	127.0.01
   smtp_sasl_security_options	Defines one or more SASL security options for the SMTP client. (Optional)	noplaintext noactive nodictionary noanonymous mutual_auth
   smtp_sasl_auth_enable	Enables/Disables SASL authentication.	yes no
   smtp_use_tls	Enables/Disables a TLS layer when available on the remote server. For more information, see the Postfix TLS Support official documentation.	yes no
   smtp_sasl_password_maps	Defines a lookup table with one or more lines, where each line contains a username:password pair, and a remote host name or a next-hop domain to identify: The Remote host name, or the next-hop domain The sender, by validating their username and password (Optional) For more information, see the Postfix official documentation.	# sasl_passwd file line examples: [ smtp.email.server.com ]:587 username:password example.com username:password
   smtp_tls_policy_maps	Defines a lookup table with one or more SMTP client TLS security policies by next-hop destination. (Optional) For more information, see the smtp_tls_policy_maps entry in main.cf(5) - Linux man page.	# tls_policy file line examples: [ smtp.email.server.com ]:587 encrypt example.gov encrypt protocols=TLSv1 example.com verify ciphers=high example.net secure

Create the password map

/etc/postfix/sasl_passwd is a text file containing a lookup table file to map the following information:

• Next-hop domain or destination SMTP host

• Email sender username

• Email sender password

To add an entry to the /etc/postfix/sasl_passwd:

1. Open the file in a text editor:

   nano /etc/postfix/sasl_passwd

2. Enter the next-hop domain or destination SMTP host, email sender username, and email sender password in the following format:

   [mail.isp.example] username:password

3. Optionally, you can specify a custom TCP port – the default mail submission port is 587:

   [mail.isp.example]:587 username:password

Create the hash file

Create the hash db file for Postfix by running the postmap command:

The command creates a new file: /etc/postfix/sasl_passwd.db.

Every time you make changes to /etc/postfix/sasl_passwd, you need to run the postmap command.

Start and enable the service

1. Enable the Postfix service to automatically start at system boot:

   systemctl enable postfix

2. Start the Postfix service:

   systemctl restart postfix

3. Verify that Postfix is up and running by checking the status:

   systemctl status postfix

Check file ownership

The default owner of /etc/postfix is root:root.