Chapter 15 Configuring Logging

This chapter briefly describes how to configure logging and view the server log. It contains the following sections:

• Log Records

• Setting Custom Log Levels

• The Logger Namespace Hierarchy

Log Records

The Application Server uses the Java 2 platform Logging API specified in JSR 047. Application Server logging messages are recorded in the server log, normally found at domain-dir/logs/server.log.

The domain-dir/logs directory contains two other kinds of logs in addition to the server log. In the access subdirectory are the HTTP Service access logs, and in the tx subdirectory are the Transaction Service logs. For information about these logs, consult the Administration Console online help.

The components of the Application Server generate logging output. Application components can also generate logging output.

Application components may use the Apache Commons Logging Library to log messages. The platform standard JSR 047 API, however, is recommended for better log configuration.

Log records follow a uniform format:

[#|yyyy-mm-ddThh:mm:ss.SSS-Z|Log Level|ProductName-Version|LoggerName|Key Value Pairs|Message|#]

For example:

[#|2004-10-21T13:25:53.852-0400|INFO|sun-appserver-e8.1|javax.enterprise.
system.core|_ThreadID=13;|CORE5004: Resource Deployed: 
[cr:jms/DurableConnectionFactory].|#]

In this example,

• [# and #] mark the beginning and end of the record.

• The vertical bar (|) separates the record fields.

• 2004-10-21T13:25:53.852-0400 specifies the date and time.

• The Log Level is INFO. This level may have any of the following values: SEVERE, WARNING, INFO, CONFIG, FINE, FINER, and FINEST.

• The ProductName-Version is sun-appserver-ee8.1.

• The LoggerName is a hierarchical logger namespace that identifies the source of the log module, in this case javax.enterprise.system.core.

• The Key Value Pairs are key names and values, typically a thread ID such as _ThreadID=14;.

• The Message is the text of the log message. For all Application Server SEVERE and WARNING messages and many INFO messages, it begins with a message ID that consists of a module code and a numerical value (in this case, CORE5004).

You can use the com.sun.enterprise.server.logging.max_history_files system property to limit the number of rotated log files for both access logging and the server log. The property specifies the maximum number of access log files to keep, starting with the most recent ones.

• If the property is not set, then no history files cleanup is done.

• If the property is set and it's either an invalid number or null, then a default of 10 history files is kept.

• If the property is set to 0, then no history files are kept.

In the Admin Console, access the config/server that this system property needs to be set for. On the command line, use the create-jvm-option command.

Setting Custom Log Levels

This section explains how to configure custom logging levels for applications that make use of the java.util.logging package and access the Application Server's logging sub system.

The java.util.logging package provides a hierarchical name space in which logger instances can be created. Whether a particular logging record is output to an Application Server instance's log file depends on the log level of the Log Record and the log level specified.

The Application Serverlogger settings configuration provides over twenty logging modules that allow fine grained control over the Application Server's own internal logging. There is also an option to create additional custom Log Modules by specifying a module name and the logging level that the module should use.

The important point here is that the logger is a static name and no inheritance is provided. Therefore, if a custom logger is configured with the name com.someorg.app and an application attempts to look up the logger com.someorg.app.submodule, then it will not be provided with a logger that inherits the settings from com.someorg.app. Instead, com.someorg.app.submodule will have a default logger that is set to log at the INFO level or higher.

If an application needs to use logger inheritance, this can be configured by editing the logging.properties file of the Java runtime that is being used to run the Application Server. For example, adding the following entry to the logging.properties file, would result in com.someorg.app.submodule inheriting the same FINE level when it is created:

com.someorg.app.level = FINE

For more details about the Java logging API, refer to the Java documentation at http://java.sun.com/j2se/1.5.0/docs/api/java/util/logging/package-summary.html, as well as the other java.util.logging classes.

The Logger Namespace Hierarchy

The Application Server provides a logger for each of its modules. The following table lists the names of the modules and the namespace for each logger in alphabetical order, as they appear on the Log Levels page of the Administration Console. The last three modules in the table do not appear on the Log Levels page.