This plugin allows you to authenticate users to remote SMTP servers bridging the original user and password to the remote server, and proxy the result back to authenticate the client.

This plugin is meant to be used with the plugin queue/smtp_bridge.

It is different than auth/auth_proxy because it doesn’t require the AUTH user in format, and it doesn’t check that the domain is the configuration file. This plugins simply takes the original user and password and tries to authenticate it in the remote SMTP server.


Configuration is stored in config/smtp_bridge.ini and uses the INI style formatting.

The configuration of this plugin is simple:

  • host: the host where you will be authenticating and posting, for example This is the only setting required.

If needed you can also set

  • port: default to empty and Haraka will use 25.

The options auth_type and priority will be used by queue/smtp_bridge