Start/notes.ini Parameters/SMTPListenerPort

SMTPListenerPort

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Parameter: SMTPListenerPort
Short description: TCP port on which the Domino SMTP listener accepts connections (default 25).

Profile

Parameter
SMTPListenerPort
Category
Mail / Router
Component
Server
Available since
9.0.1
Supported versions
9.0.1, 10.0, 11.0, 12.0, 14.0, 14.5, 14.5.1
GUI equivalent
Server document
Possible values
TCP port (typically 25, alternatively 587 for submission)

Description

By default, Domino listens on port 25, the classic SMTP inbound port. For special configurations – e.g. when a TLS-terminating proxy in front of Domino is listening on port 25 and Domino itself should be reachable on an internal port – SMTPListenerPort lets you set a different port. For mail submission from clients (authenticated sending), port 587 with STARTTLS is typically enabled in addition.

Example configuration

SMTPListenerPort=25

Notes & pitfalls

  • Also stored in the Server document; better to maintain changes there to avoid conflicts.
  • Takes effect after restarting the SMTP task (tell smtp quit / load smtp).
  • If the port is already in use (e.g. by an antispam gateway), the listener fails to start.
  • For submission / STARTTLS, additionally configure port 587 via the Internet Site / Configuration document.