The mail_server role provides a number of common configuration options that make it possible to customize the server behaviour.

However, in a number of occasions it has been necessary to add somewhat non-standard tweaks to this configuration file - and these tweaks can be quite server, deployment, or even situation-specific. Instead of forcing the role user to be applying custom changes as part of separate playbook (and violating the role idempotency), it would be better to provide ability to provide additional directives instead.

Some examples from the past experiences on using the role with Majic Infrastructure:

• Ability to increase the mail message size limit (although this is now covered by separate parameter).
• Ability to set the smtp_skip_5xx_greeting = no option to deal with RFC-breaking servers (such as t-online.de ones).

The following should be done:

• Update the mail_server role.
  • Add parameter mail_server_smtp_additional_configuration.
  • Parameter should be treated as a string appended to the end of the file. This should make it simpler to provide complex configurations when needed, and the input format will be more flexible (instead of fidgeting with lists etc).
• Update role reference documentation.
• Update release notes.