Package org.apache.hadoop.yarn.server.resourcemanager

Class ActiveStandbyElectorBasedElectorService

java.lang.Object

org.apache.hadoop.service.AbstractService

org.apache.hadoop.yarn.server.resourcemanager.ActiveStandbyElectorBasedElectorService

All Implemented Interfaces:

java.io.Closeable, java.lang.AutoCloseable, org.apache.hadoop.ha.ActiveStandbyElector.ActiveStandbyElectorCallback, org.apache.hadoop.service.Service, EmbeddedElector

@Private
@Unstable
public class ActiveStandbyElectorBasedElectorService
extends org.apache.hadoop.service.AbstractService
implements EmbeddedElector, org.apache.hadoop.ha.ActiveStandbyElector.ActiveStandbyElectorCallback

Leader election implementation that uses ActiveStandbyElector.

Nested Class Summary

Nested classes/interfaces inherited from interface org.apache.hadoop.service.Service

org.apache.hadoop.service.Service.STATE

Method Summary

Modifier and Type	Method	Description
void	becomeActive()
void	becomeStandby()
void	enterNeutralMode()	When the ZK client loses contact with ZK, this method will be called to allow the RM to react.
void	fenceOldActive(byte[] oldActiveData)
java.lang.String	getZookeeperConnectionState()	Get information about the elector's connection to Zookeeper.
void	notifyFatalError(java.lang.String errorMessage)
void	rejoinElection()	Leave and rejoin leader election.
protected void	serviceInit(org.apache.hadoop.conf.Configuration conf)
protected void	serviceStart()
protected void	serviceStop()

Methods inherited from class org.apache.hadoop.service.AbstractService

close, getBlockers, getConfig, getFailureCause, getFailureState, getLifecycleHistory, getName, getServiceState, getStartTime, init, isInState, noteFailure, putBlocker, registerGlobalListener, registerServiceListener, removeBlocker, setConfig, start, stop, toString, unregisterGlobalListener, unregisterServiceListener, waitForServiceToStop

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.hadoop.service.Service

close, getBlockers, getConfig, getFailureCause, getFailureState, getLifecycleHistory, getName, getServiceState, getStartTime, init, isInState, registerServiceListener, start, stop, unregisterServiceListener, waitForServiceToStop

Method Detail

serviceInit

protected void serviceInit(org.apache.hadoop.conf.Configuration conf)
                    throws java.lang.Exception

Overrides:

serviceInit in class org.apache.hadoop.service.AbstractService

Throws:

java.lang.Exception

serviceStart

protected void serviceStart()
                     throws java.lang.Exception

Overrides:

serviceStart in class org.apache.hadoop.service.AbstractService

Throws:

java.lang.Exception

serviceStop

protected void serviceStop()
                    throws java.lang.Exception

Overrides:

serviceStop in class org.apache.hadoop.service.AbstractService

Throws:

java.lang.Exception

becomeActive

public void becomeActive()
                  throws org.apache.hadoop.ha.ServiceFailedException

Specified by:

becomeActive in interface org.apache.hadoop.ha.ActiveStandbyElector.ActiveStandbyElectorCallback

Throws:

org.apache.hadoop.ha.ServiceFailedException

becomeStandby

public void becomeStandby()

Specified by:

becomeStandby in interface org.apache.hadoop.ha.ActiveStandbyElector.ActiveStandbyElectorCallback

enterNeutralMode

public void enterNeutralMode()

When the ZK client loses contact with ZK, this method will be called to allow the RM to react. Because the loss of connection can be noticed before the session timeout happens, it is undesirable to transition immediately. Instead the method starts a timer that will wait YarnConfiguration.RM_ZK_TIMEOUT_MS milliseconds before initiating the transition into standby state.

Specified by:

enterNeutralMode in interface org.apache.hadoop.ha.ActiveStandbyElector.ActiveStandbyElectorCallback

notifyFatalError

public void notifyFatalError(java.lang.String errorMessage)

Specified by:

notifyFatalError in interface org.apache.hadoop.ha.ActiveStandbyElector.ActiveStandbyElectorCallback

fenceOldActive

public void fenceOldActive(byte[] oldActiveData)

Specified by:

fenceOldActive in interface org.apache.hadoop.ha.ActiveStandbyElector.ActiveStandbyElectorCallback

rejoinElection

public void rejoinElection()

Description copied from interface: EmbeddedElector

Leave and rejoin leader election.

Specified by:

rejoinElection in interface EmbeddedElector

getZookeeperConnectionState

public java.lang.String getZookeeperConnectionState()

Description copied from interface: EmbeddedElector

Get information about the elector's connection to Zookeeper.

Specified by:

getZookeeperConnectionState in interface EmbeddedElector

Returns:

zookeeper connection state