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trace smtp — trace smtp transactions


trace smtp add [ binding_name ] [ domain_name ] [ file_name ]

trace smtp list

trace smtp remove [ tracer_id ]


10:47:35 /tmp/2025> trace smtp add <binding|*> <domain|*> <filename>
10:47:35 /tmp/2025> trace smtp remove <tracer_id>
10:47:35 /tmp/2025> trace smtp list

The trace smtp command allows fine-grained SMTP transaction-level logging to a specified file. It can be enabled by binding and domain combination. If * is specified for binding or domain it will match all bindings or domains, respectively.


The trace smtp command traces outbound SMTP connections only.

In order to debug SMTP transaction to, one would:

10:47:35 /tmp/2025> trace smtp add * /var/tmp/smtp.log
Registered smtp tracer #1

10:47:35 /tmp/2025> trace smtp list
[     1]  binding: *
             file: /var/tmp/smtp.log @ 29

Once sufficient debugging information has been collected, the debugging can be disabled as follows:

10:47:35 /tmp/2025> trace smtp remove 1
Removed smtp tracer #1

To set the permissions of smtp trace files see trace_smtp_mode.

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