Table of Contents
This chapter describes the basic concept and structure of JEUS SNMP. This chapter describes the relationship between the JEUS SNMP agent and the JEUS system and the relationship between JEUS SNMP agent and the JEUS JMX . This chapter also describes an SNMP manager application that exchanges messages with the SNMP agent.
SNMP stands for Simple Network Management Protocol. It is a standard protocol to monitor hardware and software in the network.
The JMX 1.2 specifications provide protocol adapter that supports SNMP. The J2EE Management 1.1 specification defines a management information base (MIB) that is used by the network or system management protocols for Internet communications.
The main components for the JEUS SNMP agent are as follows:
Communicates with the JMX Mbean server and logically resides in JEUS. JEUS SNMP agent provides base structure to manage JEUS and implements J2EE Management 1.1.
For more information about JEUS server structure, refer to "JEUS Server Guide".
SNMP Manager
Exchanges messages with the SNMP agent.
When the SNMP Manager application sends SNMP messages, the SNMP agent listens to the specified port. If a request comes through the port, the SNMP agent finds the OID in the MIB-tree to find the protocol data unit (hereafter PDU) type, and calls the JEUS JMX MBean server. When the SNMP agent receives the desired information, it returns the value to the SNMP Manager application.
The JEUS SNMP Agent module is a useful component to monitor the JEUS management system through SNMP.
As a management protocol for web application server, the JEUS SNMP agent communicates with the JEUS JMX MBean server and supports the SNMP Manager application.
The JEUS SNMP agent supports the following protocols.
The JEUS SNMP agent is fully integrated with JEUS JMX. The JEUS SNMP agent uses the JEUS JMX API to retrieve information. The SNMP agent uses the JEUS JMX API as the second-level service component of the JEUS management system, and each JEUS SNMP agent is related to one of the JVMs like a server in the JEUS system.
For example, the JMX Mbean manages the information about all modules that are deployed on the EJB engine. The SNMP Manager sends the information (JEUS SNMP OID) to the SNMP agent of an EJB engine to retrieve information about the deployed modules.
The SNMP agent instance runs as a protocol adapter for JEUS JMX and handles SNMP packets received from SNMP Manager applications. The SNMP agent also listens on the specified port for SNMP Manager requests. The listening port is specified in the JEUSMain.xml file. If the port is not specified, the SNMP agent does not run.
All agent instances work in the same way. Therefore, each agent can retrieve all information concerning JEUS management system. In order to run more than one agent instance on the same machine, the port numbers should be different.
To run the JEUS SNMP agent, the SNMP adapter port must be set.
The SNMP Manager is an application that manages a specific system, especially one that manages communication tools. In J2EE, the SNMP Manager manages enterprise applications, especially middleware like Web Application Server (WAS).
The SNMP Manager application sends management information request to the SNMP agent, with references to MIB. The application parses the MIB file to analyze the structure of the information and makes it easier for the Manager to read and manage the information.