Java Management Extensions (JMX) provide a standard mechanism to monitor and manage applications.
Spring Boot exposes the most suitable MBeanServer as a bean with an ID of mbeanServer.
Any of your beans that are annotated with Spring JMX annotations (@ManagedResource, @ManagedAttribute, or @ManagedOperation) are exposed to it.
If your platform provides a standard MBeanServer, Spring Boot will use that and default to the VM MBeanServer if necessary.
If all that fails, a new MBeanServer will be created.
See the {spring-boot-autoconfigure-module-code}/jmx/JmxAutoConfiguration.java[JmxAutoConfiguration] class for more details.