Postfix Mail Relay

Setup postfix to send via a mail relay, for example Amazon SES.

Requirements

If the chosen mail relay option is to use Amazon AWS SES, create a IAM user policy "AmazonSesSendingAccess-[username]" for the user, e.g.

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Effect": "Allow",
            "Action": [
                "ses:SendEmail",
                "ses:SendRawEmail"
            ],
            "Resource": "*"
        }
    ]
}

Role Variables

Available variables are listed below, along with default values (see defaults/main.yml):

postfix_relay_enabled: True

By default, the postfix configuration is enabled, so skip set to False.

postfix_relay_server: ""

Postfix relay server hostname, e.g. "email-smtp.region.amazonaws.com".

postfix_relay_port: 587

Postfix relay server port.

postfix_myhostname: False

The myhostname parameter specifies the internet hostname of this mail system. The default is to use the fully-qualified domain name from gethostname(). $myhostname is used as a default value for many other configuration parameters.

postfix_mydomain: False

The mydomain parameter specifies the local internet domain name. The default is to use $myhostname minus the first component. $mydomain is used as a default value for many other configuration parameters.

postfix_myorigin: False

The myorigin parameter specifies the domain that locally-posted mail appears to come from. The default is to append $myhostname, which is fine for small sites. If you run a domain with multiple machines, you should (1) change this to $mydomain and (2) set up a domain-wide alias database that aliases each user to user@that.users.mailhost.

For the sake of consistency between sender and recipient addresses, myorigin also specifies the default domain name that is appended to recipient addresses that have no @domain part.

postfix_relay_recipient_canonical_maps: regexp:/etc/postfix/recipient_canonical_maps

Address mapping lookup table for envelope and header recipient addresses using recipient_canonical_maps. By default this uses the regexp table type.

postfix_relay_recipient_canonical: []
#    - pattern: "/./" (Required)
#      address: "redirect@email.domain" (Required)

List of canonical recipients based on the regular expression tables format.

postfix_relay_recipient_canonical_classes: envelope_recipient

Addresses subject to canonical_maps address mapping. Specify one or more of: envelope_sender, envelope_recipient, header_sender, header_recipient.

postfix_relay_catch_all_address: False
# postfix_relay_catch_all_address: redirect@email.domain

Email address to redirect all email. By default this is disabled and should generally only be enabled in development environments. If specified this will overwrite all postfix_relay_recipient_canonical items.

postfix_relay_catch_all_pattern: /./

Default (regexp) pattern used to trap all emails and send to the catch all address.

postfix_virtual_alias_maps:
   - address: root
     alias: root@localhost

Deliver mail to local accounts by setting up virtual aliases. By default, any mail to root will be sent to root@localhost (delivered locally). Disable all default aliases by setting this value to False.

postfix_relayhost_maps: []
#    - domain: "@domain.com" (Required)
#      server: "" (Optional, defaults to postfix_relay_server)
#      port: 587 (Optional, defaults to postfix_relay_port)
#      user: "user-here" (Optional, defaults to postfix_relay_user)
#      password: "password-here" (Optional, defaults to postfix_relay_password)

Enables smtp_sender_dependent_authentication to allow mail to be relayed through multiple hosts with different credentials, depending on the sender email address. Note that the domain value can be specified as a full address user@domain.com or wildcard using @domain.com. (See postfix relayhost_map documentation.)

postfix_relay_user: ""

Set postfix relay user.

postfix_relay_password: ""

Set the relay server password.

postfix_relay_secret_key: "secret-key-here"

Generate the relay password from specified AWS Secret Key. Or, manually populate the postfix_relay_password value by converting an existing AWS Secret Key to an Amazon SES SMTP password using the included bash script:

./scripts/aws-ses-smtp-password.sh secret-key-here

Dependencies

None.

Example Playbook

Including an example of how to use your role (for instance, with variables passed in as parameters) is always nice for users too:

- hosts: servers
  become: yes
  vars_files:
    - vars/main.yml
  roles:
    - memiah.mail-relay

Inside vars/main.yml:

postfix_relay_user: "user_here"
postfix_relay_password: "password_here"
postfix_relay_server: "email-smtp.region.amazonaws.com"

License

MIT / BSD

Author Information

This role was created in 2016 by Memiah Limited.