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Variables

Context or environment variables may be used in certain settings of the configuration file that accept expressions. The available context variables for evaluation vary depending on the setting and can include:

  • remote_ip: The IP address of the client for inbound sessions and the remote server's IP address for outbound sessions.
  • remote_port: The remote clients's port number for an inbound session.
  • local_ip: The local server's IP address used in an outbound connection (available only when a source IP is specified).
  • local_port: The local server's port number for an inbound connection.
  • listener: The listener ID where the connection was initiated for inbound sessions.
  • is_tls: A boolean value indicating whether the session is encrypted using TLS.
  • protocol: The protocol used for the session (smtp, imap, http, etc.).
  • sender: The return path address specified in the MAIL FROM command for inbound sessions and the sender's address for outbound sessions.
  • sender_domain: The return path domain name specified in the MAIL FROM command for inbound sessions and the sender's domain name for outbound sessions.
  • rcpt: The recipient's address.
  • rcpt_domain: The recipient's domain name.
  • recipients: An array of recipient addresses.
  • priority: The priority provided using the MT-PRIORITY extension.
  • authenticated_as: The account name used to authenticate the session for inbound sessions, or an empty value if the session is unauthenticated.

Queue Variables​

The following additional variables are available for use in queue expressions:

  • mx: The remote mail exchanger's hostname for outbound sessions.
  • retry_num: The number of times the message has been retried.
  • notify_num: The number of times the sender of the message has been notified.
  • last_error: The last error message type encountered during delivery attempts.
  • last_status: The last status code returned by the remote server during delivery attempts.