The latest stable release of the widely adopted mail transport agent (MTA) Postfix, version 3.9, introduces a series of enhancements and changes, maintaining the tradition of offering robust and secure email solutions. Here are the most important of them.
Key Updates in Postfix 3.9 MTA
Postfix 3.9 encompasses several major enhancements across various areas, including database support, environmental variables (ENVID) support, feature deprecation, MIME conversion, protocol compliance, security measures, and TLS support.
- Database Support: Potsfix 3.9 now offers MongoDB client support. In addition, this release is also complemented by more flexible timer settings for MySQL and PostgreSQL clients, improving Postfix’s adaptability to various database environments. Additionally, the release discontinues support for MySQL versions older than 4.0.
- Enhanced ENVID Support: The local and pipe delivery agents now support exporting and utilizing the RFC 3461 envelope ID, enhancing message tracking capabilities.
- Feature Deprecation: A new document outlines removing specific features and provides migration paths, ensuring users can smoothly transition to newer alternatives.
- MIME Conversion: A new parameter, “force_mime_input_conversion,” addresses the need for content conversion before various checks and filters, aiding in maintaining the integrity of outbound message signatures.
- Protocol Compliance: Adjustments have been made to align with RFC 5322 date and time specifications, requiring numerical days to be formatted with a leading zero.
- Security Improvements: Several measures have been implemented to enhance security, such as limiting DNS lookup results and introducing settings to prevent SMTP smuggling attacks.
- TLS Support: Optional support for RFC7250 raw public keys in TLS communication introduces flexibility in certificate management, a step towards modernizing secure email exchanges.
Upgrading users, especially those moving from version 3.7 or earlier, are advised to consult the release notes for critical information. The release also details feature deprecations, urging users to migrate away from obsolete functionalities to ensure a smoother transition and maintain the integrity of email services.
