sendmail, 4th Edition

Milter Logging with syslog

The Milter library performs no logging. If you wish to have the activities of your Milter logged, you must include that support into the Milter you create.

The sendmail program, on the other hand, does have the ability to log its interaction with Milters. That logging is enabled and its volume tuned using the Milter.LogLevel option (Milter.LogLevel on page 1053). It is declared like this:

O Milter.loglevel=level                 ← configuration file
-OMilter.loglevel=level                   ← command line
define(`confMILTER_LOG_LEVEL',`level')    ← mc configuration

Here, level is an integer that determines what and how much will be logged. In general, levels less than 10 are logged at LOG_ERR, and those greater than 10 are logged at LOG_INFO. A level of 0 disables logging. Table 26-6 shows the currently defined levels and what will be logged at each level. Note that each level also logs the information that is logged at the levels below it.

Table 26-6. Milter.LogLevel option settings

Milter.LogLevel	Screens what
1	Bad reply codes from the external program, socket errors, timeouts, and errors generally.
9	Added or deleted a header or RCPT To: response, replaced message body, etc. This is the default level..
10	Connection information.
11	Reply rejects, temp-fails, and deferrals.
14	Reply codes.
15	Milter senders, and Milter recipients.
18	Headers sent, and body sent.
22	Time to complete a command.