org.opennms.netmgt.poller.monitors

Class NtpMonitor

java.lang.Object

org.opennms.netmgt.poller.support.AbstractServiceMonitor

org.opennms.netmgt.poller.monitors.NtpMonitor

All Implemented Interfaces:

ServiceMonitor

@Distributable
public final class NtpMonitor
extends AbstractServiceMonitor

This class is designed to be used by the service poller framework to test the availability of the NTP service on remote interfaces. The class implements the ServiceMonitor interface that allows it to be used along with other plug-ins by the service poller framework.

Author:

Tarus Balog , OpenNMS

Constructor Summary

Constructors

Constructor and Description
NtpMonitor()

Method Summary

Modifier and Type	Method and Description
PollStatus	poll(MonitoredService svc, Map<String,Object> parameters) This method is the heart of the plug-in monitor.

Methods inherited from class org.opennms.netmgt.poller.support.AbstractServiceMonitor

getEffectiveLocation, getKeyedBoolean, getKeyedInstance, getKeyedInteger, getKeyedLong, getKeyedObject, getKeyedString, getRuntimeAttributes, getServiceProperties

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

NtpMonitor

public NtpMonitor()

Method Detail

poll

public PollStatus poll(MonitoredService svc,
                       Map<String,Object> parameters)

This method is the heart of the plug-in monitor. Each time an interface requires a check to be performed as defined by the scheduler the poll method is invoked. The poll is passed the service to check.

By default when the status transition from up to down or vice versa the framework will generate an event. Additionally, if the polling interval changes due to an extended unavailability, the framework will generate an additional down event. The plug-in can suppress the generation of the default events by setting the suppress event bit in the returned integer.

NOTE: This method may be invoked on a Minion, in which case certain bean and facilities will not be available. If any state related information is required such as agent related configuration, it should retrieved by the ServiceMonitor.getRuntimeAttributes(MonitoredService, Map).

Poll the specified address for NTP service availability.

During the poll an NTP request query packet is generated. The query is sent via UDP socket to the interface at the specified port (by default UDP port 123). If a response is received, it is parsed and validated. If the NTP was successful the service status is set to SERVICE_AVAILABLE and the method returns.

Parameters:

svc - Includes details about to the service being monitored.

parameters - Includes the service parameters defined in poller-configuration.xml and those returned by ServiceMonitor.getRuntimeAttributes(MonitoredService, Map).

Returns:

The availability of the interface and if a transition event should be suppressed.

See Also:

PollStatus.SERVICE_AVAILABLE, PollStatus.SERVICE_UNAVAILABLE, PollStatus.SERVICE_AVAILABLE, PollStatus.SERVICE_UNAVAILABLE