|Managing Pivotal GemFire / GemFire Management and Monitoring|
GemFire's management and monitoring system consists of one JMX Manager node (there should only be one) and one or more managed nodes within a distributed system. All members in the distributed system are manageable through MBeans and GemFire Management Service APIs.
The following diagram depicts the architecture of the management and monitoring system components.
In this architecture every GemFire member is manageable. All GemFire MBeans for the local GemFire processes are automatically registered in the Platform MBeanServer (the default MBeanServer of each JVM that hosts platform MXBeans.)
A JMX Manager node is a member that can manage other GemFire members --that is, other managed nodes -- as well as itself. A JMX Manager node can manage all other members in the distributed system.
To convert a managed node to a JMX Manager node, you configure the GemFire property jmx-manager=true, in the gemfire.properties file, and start the member as a JMX Manager node. You start the member as a JMX Manager node when you provide --J=-Dgemfire.jmx-manager=true as an argument to either the start server or start locator command. See Starting a JMX Manager for more information.
Management and monitoring tools such as the GemFire SHell (gfsh) and GemFire Pulse use JMX/RMI as the communication layer to connect to GemFire nodes. All GemFire processes by default allow JMX connections to the Platform MBeanServer from localhost. By default, both managed nodes and JMX manager nodes have RMI connectors enabled to allow JMX client connections.
JConsole (and other similar JMX clients that support Sun's Attach API) can connect to any local JVM without requiring an RMI connector by using the Attach API. This allows connections from the same machine.
JConsole (and other JMX clients) can connect to any JVM if that JVM is configured to start an RMI connector. This allows remote connections from other machines.
JConsole can connect to any GemFire member, but if it connects to a non-JMX-Manager member, JConsole only detects the local MBeans for the node, and not MBeans for the cluster.
When a GemFire locator or server becomes a JMX Manager for the cluster, it enables the RMI connector. JConsole can then connect only to that one JVM to view the MBeans for the entire cluster. It does not need to connect to all the other JVMs. GemFire manages the inter-JVM communication required to provide a federated view of all MBeans in the distributed system.
GemFire SHell (gfsh) can only connect to a JMX Manager or to a locator. If connected to a locator, the locator provides the necessary connection information for the existing JMX Manager. If the locator detects a JMX Manager is not already running in the cluster, the locator makes itself a JMX Manager. gfsh cannot connect to other non-Manager or non-locator members.
For information on how to configure the RMI registry and RMI connector, see Configuring RMI Registry Ports and RMI Connectors.
GemFire management APIs represent the Gemfire cluster to a JMX user. However, they do not provide functionality that is otherwise present in JMX. They only provide a gateway into various services exclusively offered by GemFire monitoring and management.
ManagementService service = ManagementService.getManagementService(cache);
The resulting ManagementService instance is specific to the provided cache and its distributed system. The implementation of getManagementService is a singleton for now but may eventually support multiple cache instances.
See the JavaDocs for the com.gemstone.gemfire.management package for more details.
You can also execute gfsh commands using the ManagementService API. See Executing gfsh Commands through the Management API and the JavaDocs for the com.gemstone.gemfire.management.cli package.