org.rhq.enterprise.server.storage

Class StorageClusterHeartBeatJob

java.lang.Object

org.rhq.enterprise.server.storage.StorageClusterHeartBeatJob

public class StorageClusterHeartBeatJob
extends Object

This job runs periodically to verify that the server can connect to the storage cluster. If the server cannot connect to any nodes in the cluster, the server will be put into maintenance mode until it is able to connect to the cluster. See checkClusterHeartBeat() for more details.

Author:

John Sanda

Constructor Summary

Constructors

Constructor and Description
StorageClusterHeartBeatJob()

Method Summary

Methods

Modifier and Type	Method and Description
void	checkClusterHeartBeat() Runs periodically to verify that the server can connect to the storage cluster.
void	scheduleJob()

Methods inherited from class java.lang.Object

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

Constructor Detail

StorageClusterHeartBeatJob

public StorageClusterHeartBeatJob()

Method Detail

scheduleJob

public void scheduleJob()

checkClusterHeartBeat

public void checkClusterHeartBeat()

Runs periodically to verify that the server can connect to the storage cluster. If the server cannot connect to any nodes in the cluster, the server will be put into maintenance mode until a connection can be made to the cluster.

While client requests are made using CQL commands going over the native transport layer introduced in Cassandra 1.2, connectivity is checked via JMX. The JMX call is made to determine whether or not the native transport is running. Trying to do the check using the CQL driver gets complicated and introduces some non-trivial overhead due to the fact that the driver is async.