Log diagnostics MTA option

Transaction logging MTA options:  (0-3)
(New in 7.0-3.01.) Bit 0 (value 1), if set in,  causes diagnostics information to appear in certain log entries. Bit 1 (value 2), if set, causes diagnostics information to be included in   mapping probes. For instance, in the case of "B" records (bad commands received by the SMTP server), the diagnostic field will show the SMTP server error response. In the case of connection close "C" records, the diagnostic file will show the reason why the connection was closed, e.g., reaching some session disconnect limit. In the case of authentication " " entries (which note are generated as connection transaction entries, rather than message transaction entries), the result of an authentication attempt is shown in the diagnostic field. Appears just after the reason field (see the  MTA option) and before the time-in-queue field (see the   MTA option). In XML or JSON format (  set to 4 or 5, respectively), diagnostic information, if enabled, appears as the   attribute.

Normally the  attribute only appears in XML or JSON format logs if there is diagnostic information to log. As of MS 8.0.2.3, setting bit 2 (value 4) will cause the attribute to appear unconditionally.

This option defaults to 1 in order to maintain compatibility with previous releases, where diagnostics information was always logged.

See also:
 * Transaction logging MTA options
 * Triggering effects from transaction logging with LOG_ACTION
 * MTA transaction logging
 * log_reason MTA Option
 * log_remote_mta MTA Option
 * log_queue_time MTA Option
 * log_format MTA Option