Agent & PDK

The Professional Open Source™ Company

Agent & PDK

JBossNetwork Enterprise Manager

2 The Professional Open Source™ Company

Agenda

• Overview of the Agent Architecture• Server Agent communications• Plugin Development Kit

MX4J Example


• The JBN EM Server Controls all agents Provides the user interface for

interactive monitoring Tracks and stores historical

information including metrics data and control history

Provides security and access control to agent features

Agent overview


Agent overview

• JBN EM Agent Acts on behalf of the server Organizes auto-inventory scans Collects metrics information according to

the server configured schedule Accumulated metrics information is

streamed to the server on a regular basis


Server agent communication

JBN EM

Server

Platform AJBN EM

Agent

JBoss A

JBoss BApache

Platform BJBN EM

Agent

JBoss A

JBoss B

Apache

Platform CJBN EM

Agent

JBoss

Tomcat

Apache

plugins

ControlMetrics


Plugin overview

• A JBN EM Plugin is a self-contained jar or xml file representing a platform, server or service that can be monitored

• They include metadata about the inventory hierarch of these resource types in the form of an xml descriptor

• This metadata is loaded by both the server and the agent

• Plugin hooks are available for Measurement (metrics) Control Auto Inventory Response Time


Plugin descriptor

• The plugin descriptor is named “hq-plugin.xml” when deployed in a plugin jar

<plugin package="net.hyperic.hq.product.mx4j">

<property name="template-config“ value="jmxUrl=%jmxUrl%"/>

<filter name="ServerInfo“ value="hyperic:type=ServerInfo"/>

<server name="Example Server“ version="1.0"

description="Example MX4J 3.0 Based Server">



<plugin type="measurement“ class="MX4JMeasurementPlugin"/>

<plugin type="autoinventory“ class="MX4JDetector"/>

…


Plugin services

• Metrics are defined against platforms, servers and services

….

<service name="Echo Service">

<plugin type="control“ class="MX4JControlPlugin"/>

<config>

<option name="service.name"

description="Service Name"

default=""/>

</config>

<actions include="start,stop"/>

<metrics include="echo-service"/>

</service>

…


Plugin metrics

• Metrics are point in time recordings of numeric information from a resource

• Metrics are defined against resources in the descriptor

• The server can manage metrics templates that define the default collection interval

• The server can define custom collection intervals for a specific sevice


Plugin metrics

….

<metrics name="echo-service“>

<metric name="Availability"

alias="Availability"

template="${EchoService},name=%service.name%:${alias}"

category="AVAILABILITY"

defaultOn="true"

indicator="true"

units="percentage"

collectionType="dynamic"/>

<metric name="Uptime"

alias="Uptime"

template="${EchoService},name=%service.name%:${alias}"

category="AVAILABILITY"

defaultOn="true"

indicator="false"

units="ms"

collectionType="static"/>

</metrics>


Plugin metrics implementation

public class MX4JMeasurementPlugin extends MeasurementPlugin {

public MetricValue getValue(Metric metric)

throws PluginException,

MetricNotFoundException,

MetricUnreachableException

{

String jmxUrl = metric.getProperties().getProperty(PROP_JMXURL);

String objectName = metric.getObjectName();

String attribute = metric.getAttributeName();

JMXServiceURL url = new JMXServiceURL(jmxUrl);

JMXConnector connector = JMXConnectorFactory.connect(url);

MBeanServerConnection conn = connector.getMBeanServerConnection();

ObjectName objName = new ObjectName(objectName);

return conn.getAttribute(objName, attribute);

double val = Double.valueOf(obj.toString()).doubleValue();

return new MetricValue(val);

} …


Example metrics defaults


Plugin controls

• Below is an example of resource control provided by a plugin

• This plugin implements three control actions, start, stop and reload via <actions include="start,stop,restart"/>

• These actions can be scheduled and are historically tracked


Plugin controls implementation

public void doAction(String action) throws PluginException {

String jmxUrl = this.config.getValue(MX4JUtil.PROP_JMXURL);

String name = this.config.getValue(MX4JDetector.PROP_SERVICE_NAME);

String object = "hyperic:type=EchoServer,name=" + name;

// Default to error

setResult(RESULT_FAILURE);

if (action.equals("start")) {

setState(STATE_STARTING);

MX4JUtil.invoke(jmxUrl, object, action);

setResult(RESULT_SUCCESS);

setState(STATE_STARTED);

} else if (action.equals("stop")) {

setState(STATE_STOPPING);

MX4JUtil.invoke(jmxUrl, object, action);

setResult(RESULT_SUCCESS);

setState(STATE_STOPPED);

}

}


Plugin autoinventory

• The autoinventory plugin can search for known services using means appropriate to the service HTTP server management could attempt

connection to an admin URL on port 80 for example

• Autoinventory plugins can also configure file system properties to integrate with the search architecture

• Implements List discoverServices(ConfigResponse serverConfig)


Review

• We’ve covered The Server/Agent architecture of JBN EM The Server management and display of

metrics collection, control operation and autoinventory

The Agent plugin architecture including• The execution of plugin implementations• The definition of resource metadata• The implementation of metrics gathering


Thanks for your time!

Q & A

Documents

Agent & PDK