The SyslogStartConverter class is a part of the Logback library that can be used to include information from the Syslog protocol in the log message. It formats a log event as a Syslog packet, including the priority, timestamp, hostname, and other fields.

Here is an example of how you might use the SyslogStartConverter in a Logback configuration file:

<configuration>
  <conversionRule conversionWord="syslogStart" converterClass="ch.qos.logback.classic.pattern.SyslogStartConverter"/>

  <appender name="CONSOLE" class="ch.qos.logback.core.ConsoleAppender">
    <encoder>
      <pattern>%syslogStart %msg%n</pattern>
    </encoder>
  </appender>

  <root level="debug">
    <appender-ref ref="CONSOLE" />
  </root>
</configuration>

This configuration file sets up a CONSOLE appender that outputs log messages in the format "%syslogStart %msg%n". The %syslogStart part of the pattern is where the Syslog information is inserted into the log message.

The SyslogStartConverter uses the SyslogAppenderBase class, which provides the conversion of priority to facility-priority value.

Please note that, the output will be written to the console in this example, you can use file based appender to output the logs to a file. And you can refer to the logback documentation for more information and options available.