MBeans in Weblogic Server

System administration infrastructure in WebLogic Server is implemented using the Java Management Extension (JMX) specification from Sun Microsystems. The JMX API models system administration functions with Java objects called MBeans.

There are three types of MBeans used to manage a WebLogic Server domain:

1. Administration
2. Configuration
3. Runtime Mbeans

Administration Mbeans :

It contain a set of attributes that define configuration parameters for various management functions. All attributes for administration MBeans have pre-set default values. When the Administration Server starts, it reads a file called config.xml and overrides the default attribute values of the administration MBeans with any attribute values found in the config.xml file.


The config.xml file, located on the machine that hosts the Administration Server, provides persistent storage of Mbean attribute values. Every time you change an attribute using the system administration tools, its value is stored in the appropriate administration MBean and written to the config.xml file. Each WebLogic Server domain has its own config.xml file.

If you set any configuration attributes on the command line when you start the Administration Server using the -D arguments, these values override the values set by the defaults or those read from the config.xml file. These overridden values are also persisted to config.xml file by the Administration Server.

Configuration Mbeans :

It's copies of Administration Mbeans that each Managed Server uses to initialize its configuration. When you start a Managed Server, the server receives a copy of the of all the administration MBeans from the Administration Server and stores them in memory as configuration MBeans. If you override any configuration attributes when starting a Managed Server, those values override the values received from the Administration Server but are not written to the config.xml file.

Runtime Mbeans :

It contain sets of attributes consisting of runtime information for active WebLogic Servers instances and applications. By retrieving the values of attributes in these runtime MBeans, you can monitor the running status of a WebLogic Server domain.

Mbeans may also contain operations used to execute management functions.