25-logging

  #
  # NB log_selector can only appear once
  # Remove the setting in 00-main/50-tls-options
  # Set logging values
  # This improves picking up attempts to get logins

  # Logging arguments are:
  # 
  # tls_sni: When a message is received over an encrypted connection, and
  # the remote host provided the Server Name Indication extension, the SNI
  # is added to the log line, preceded by SNI=.
  # 
  # smtp_protocol_error: A log line is written for every SMTP protocol
  # error encountered. Exim does not have perfect detection of all
  # protocol errors because of transmission delays and the use of
  # pipelining. If PIPELINING has been advertised to a client, an Exim
  # server assumes that the client will use it, and therefore it does not
  # count “expected” errors (for example, RCPT received after rejecting
  # MAIL) as protocol errors.
  # 
  # incoming_interface: The interface on which a message was received is
  # added to the “<=” line as an IP address in square brackets, tagged by
  # I= and followed by a colon and the port number. The local interface
  # and port are also added to other SMTP log lines.
  # 
  # smtp_mailauth: A third subfield with the authenticated sender,
  # colon-separated, is appended to the A= item for a message arrival or
  # delivery log line, if an AUTH argument to the SMTP MAIL command was
  # accepted or used.
  # 
  # This from https://www.exim.org/exim-html-current/doc/html/spec_html/ch-log_files.html

  log_selector = +tls_sni +smtp_protocol_error +incoming_interface +smtp_mailauth

  # In addition, suppress the annoying logging from the sympl test suite, the
  # test suite is fine, the logs it generates are annoying.
  hosts_connection_nolog = ::1