org.apache.hadoop.ha

Class PowerShellFencer

java.lang.Object

org.apache.hadoop.conf.Configured

org.apache.hadoop.ha.PowerShellFencer

All Implemented Interfaces:

Configurable, FenceMethod

public class PowerShellFencer
extends Configured
implements FenceMethod

Fencer method that uses PowerShell to remotely connect to a machine and kill the required process. This only works in Windows. The argument passed to this fencer should be a unique string in the "CommandLine" attribute for the "java.exe" process. For example, the full path for the Namenode: "org.apache.hadoop.hdfs.server.namenode.NameNode". The administrator can also shorten the name to "Namenode" if it's unique.

Constructor Summary

Constructors

Constructor and Description
PowerShellFencer()

Method Summary

Modifier and Type	Method and Description
void	checkArgs(String argStr) Verify that the given fencing method's arguments are valid.
boolean	tryFence(HAServiceTarget target, String argsStr) Attempt to fence the target node.

Methods inherited from class org.apache.hadoop.conf.Configured

getConf, setConf

Methods inherited from class java.lang.Object

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

Constructor Detail

PowerShellFencer

public PowerShellFencer()

Method Detail

checkArgs

public void checkArgs(String argStr)
               throws BadFencingConfigurationException

Description copied from interface: FenceMethod

Verify that the given fencing method's arguments are valid.

Specified by:

checkArgs in interface FenceMethod

Parameters:

argStr - the arguments provided in the configuration. This may be null if the operator did not configure any arguments.

Throws:

BadFencingConfigurationException - if the arguments are invalid

tryFence

public boolean tryFence(HAServiceTarget target,
                        String argsStr)
                 throws BadFencingConfigurationException

Description copied from interface: FenceMethod

Attempt to fence the target node.

Specified by:

tryFence in interface FenceMethod

Parameters:

target - the target of the service to fence

argsStr - the configured arguments, which were checked at startup by FenceMethod.checkArgs(String)

Returns:

true if fencing was successful, false if unsuccessful or indeterminate

Throws:

BadFencingConfigurationException - if the configuration was determined to be invalid only at runtime