Docker container logging is enabled by configuring a console appender in an application. For example:

<xml version="1.0" encoding="UTF-8"?>
<configuration>
    <appender name="Console" class="ch.qos.logback.core.ConsoleAppender">
        <encoder>
            <pattern>%d{HH:mm:ss.SSS} %10.10thread %-5level %20.20logger{5} : %msg%n</pattern>
        </encoder>
    </appender>
    <root level="INFO">
        <appender-ref ref="Console" />
    </root>
</configuration>

When the container containing the application is started it must have a pseudo-tty allocated for the console appender to work correctly. This is done using the tty parameter to the run command:

docker run --tty --detach --name A.sb10 --network demo-network sb10-demo-application A.sb10

When the container is started all engine logging will be sent to the container logs as shown in Figure 2.11, “Docker container logging”.

Figure 2.11. Docker container logging

Container logging is also available from the docker command line using the logs command:

docker logs --follow A.sb10

Log configuration uses standard Logback XML or Groovy configuration files with a few extensions. See the Logback configuration documentation for details on the standard configuration values.

The supported extensions are:

While it is possible to move the location of the engine log files outside of the <node-directory>/logs directory using configuration, if this is done, engine log messages are sent to both the configured location of the engine log file and also the default engine log in the logs directory. This is done to ensure that snapshot files include all logging from the node for diagnostic purposes. If an engine log file is configured to not use the default engine log file name, but the log file is left in the logs directory, only the configured log file name is used.

This example shows the use of these extensions in a Logback XML configuration file.

<?xml version="1.0" encoding="UTF-8"?>
<configuration>
  <appender name="FILE" class="ch.qos.logback.core.FileAppender">
    <file>${com.tibco.ep.dtm.logging.logDirectory}/${com.tibco.ep.dtm.logging.logFileNamePrefix}.log</file>
    <encoder>
      <pattern>d{HH:mm:ss.SSS} %usec %process %thread %transaction %-5level %logger: %msg%n</pattern>
    </encoder>
  </appender>
  <root level="INFO">
    <appender-ref ref="FILE"/>
  </root>
</configuration>
      

Logging configuration is processed in this order:

The Logback configuration file resolution rules use the standard LogBack conventions described here. The logging configuration can also be changed at runtime using the logging administration target. See the section called “Administration”.

Details on packaging logging configuration into fragment and application archives is in the Transactional Memory Developers Guide.

The runtime logging level can be changed using the logging administration target. There is support for both getting and setting the current log level for all loggers running in each engine in a node.

	The ROOT logger defines the default value that all loggers inherit. Once a logger has been created, changing the ROOT logger logging level has no affect on existing loggers. The reset logging command can be used to cause a specific logger to reset its log level to use the ROOT logger default logging level value.

To set the log level for a logger, the logger name must be known. The loggers that are displayed using the display logging command were:

For example:

//
//    Get loggers and logging level for the Pattern_sbapp0 engine
//
epadmin --servicename=A.X display logging --enginename=Pattern_sbapp0
Engine Name = Pattern_sbapp0
Logger Name = ROOT
Log Level = INFO

Engine Name = Pattern_sbapp0
Logger Name = com.sun.jersey
Log Level = WARN

Engine Name = Pattern_sbapp0
Logger Name = com.tibco.ep.dtm.audit
Log Level = INFO

Engine Name = Pattern_sbapp0
Logger Name = org.apache.shiro
Log Level = DEBUG

//
//    Set the ROOT logging level to DEBUG for all engines
//
epadmin --servicename=A.X set logging --loggername=ROOT --level=DEBUG
Engine Name = Pattern_sbapp0
Logger Name = ROOT
Previous Log Level = INFO
New Log Level = DEBUG

Engine Name = System::administration
Logger Name = ROOT
Previous Log Level = INFO
New Log Level = DEBUG

//
//    Load a new log configuration file on all engines
//
epadmin --servicename=A.X --set logging --configuration=new-logging-config.xml

Complete details on the logging target can be found in the section called “logging target”.