On 03 January 2025, PowerMTA 6.0r2 was released. This PowerMTA update simplifies configuration with automatic MX rollups, adds a REST API for virtual MTA management and improves the scalability of accounting webhooks with concurrent HTTP connections. For more details and a complete list of changes, see below.

All PowerMTA users who have an active support subscription and a PowerMTA 6.0 license can access PowerMTA 6.0r2 at Bird's download portal. If you do not have a 6.0 license, please contact us for information on updating your license. Here's what's new in the 6.0r2 release:

Automatic MX rollup configuration

Introduced automatic MX rollups to simplify configuration and maintenance compared to manual MX rollups. Refer to the global auto-mx-rollup directive for more details.

Dynamic Virtual MTA configuration

Introduced a new REST API for managing virtual MTA configurations, providing a more flexible way to create, read, update or delete virtual MTA settings.

Scalable HTTP accounting webhooks

Enhanced HTTP accounting webhooks to support concurrent connections, improving performance and scalability. Refer to the acct-file.http-webhook-max-connections directive for more details.

Enhanced Proxy integration

• Added HAProxy protocol support for inbound traffic, allowing PowerMTA to identify the originating IP address of clients connecting through the proxy. Refer to smtp-listener.use-inbound-proxy and transmissions-api-listener.use-inbound-proxy directives for more details.
• Added proxy.retry-attempts directive to customize the number of retry attempts before failing over to the next proxy.

Improved security

Extended domain.smtp-client-certificate directive to allow intermediate certificates, offering greater flexibility.

Improved diagnostics

• Extended the pmta_smtp_transient_queue_errors_total Prometheus metric to include a label for proxy-specific errors, allowing for better visibility into connection errors with proxy servers.
• Added the MX rule that matched the IP address to the accounting records when rollup-by-ip is used with MX rollup.
• Introduced the global time-first-attempt-hires-timestamp directive to enable millisecond precision in Time To First Attempt (TTFA) logged in accounting files.

Bug fixes

• Fixed an issue causing the pmta trace command to hang when the traced queue is empty.
• Fixed a bug that resulted in messages to invalid domains becoming stuck, specifically for domains with incorrect punycode.
• Resolved an incompatibility with older TLS implementations, addressing issues with HTTP accounting webhooks not functioning properly with legacy servers, as well as PMC registration errors with PowerMTA 6.0.

For a complete list of changes since 6.0, please refer to the release notes and the changelog or contact us.
We can also help you with upgrading to PowerMTA 6.0 or tuning your PowerMTA infrastructure.