Overview
Currently, there is not a good way of surfacing Geronimo's server information so that an administrator can monitor the server's status. The architecture of using MBeans is established, but not fully exploited. This enhancement will take advantage of what Geronimo currently offers and extend it so that a server can tap into a cluster of servers and extract information from specific Geronimo servers or even aggregates of Geronimo servers.
The goal is to have at least one machine be able to reach out to all Geronimo servers in order to fetch data or even alter their state. This will be especially useful in the case of someone having to monitor a large number of Geronimo servers.
How it works
As part of the design, there are five major components.
Management Node(s): An instance of Geronimo that has sole purpose of managing and viewing information from Server Nodes, must include admin console.
Management Plugin: Will reside on all Management Nodes and will handle the connection to the Remote Control Plugin to pull relevant information and control the machine.
Connection Information DB: Resides on either a Management Node or a different database server, has Server Name, IP:Port information and JMX Authentication information for all Server Nodes. Management Nodes use this information to connect to the Server Nodes
Server Node(s): An instance of Geronimo that runs as usual, can be Little G with our MBean and anywhere up from there.
Remote Control Plugin: Will be present on all Server Nodes, handle statistics collection, control the thread which takes snapshots of the server's current state.
The proposed solution would incorporate a scalable design, using the same methods to keep track of statistics and read them locally that it would be pulling them remotely from N machines. This is accomplished by creating a centralized MBean (Remote Control Plugin) that will work to be a tie-in point for all the statistics, taking a 'snapshot' of the current state of things every X minutes and recording in a database or XML file for a predetermined amount of time before there is rollover. With this MBean serving as a relay point for this data, we can simply connect to it via JMX through the Management Plugin, or a different remote machine (i.e. a proposed 'management node') to pull the information, as well as gain control over functions such as simple start/stop/restart, or in the future could be expanded to deploying/uninstalling/redeploying across an entire cluster.
Due to the use of JMX, there will not be an active connection from the management node to the server nodes at all times, and will instead be an on-demand connection that will be used only when control or information is requested, resulting in little network overhead.
UML Diagram