OpenSMTPD

The Wodby OpenSMTPD catalog stack provides an SMTP relay service on internal port 25. It can also be included in application stacks such as Drupal, WordPress, and Matomo. The current service definition is documented in wodby/stack-opensmtpd.

Production delivery

Do not rely on direct delivery from a Kubernetes node or cloud-cluster IP for production mail. Recipient providers may reject or classify mail from those addresses as spam.

Create an SMTP provider integration, then attach it to the OpenSMTPD app service's Third-party SMTP server for Relay integration. Wodby supplies the relay host, port, protocol, username, and password from the selected provider.

Applications in the same app instance should connect through their stack link. The usual internal connection is the OpenSMTPD app-service hostname on port 25; linked PHP services receive that connection automatically through their mail-transfer-agent link.

Send a test message

Open a web terminal on the OpenSMTPD service, then send a small message:

printf 'Subject: Wodby SMTP test\n\nOpenSMTPD relay test.\n' | \
  sendmail -v -f [email protected] [email protected]

Use a sender accepted by the configured provider. The verbose output confirms whether OpenSMTPD accepted the message; use the app logs and your provider's delivery logs to diagnose later relay or delivery failures.

Add the optional spool volume when queued mail must survive pod replacement.