Package org.apache.hadoop.ha

Class NodeFencer

java.lang.Object

org.apache.hadoop.ha.NodeFencer

@Private
@Evolving
public class NodeFencer
extends java.lang.Object

This class parses the configured list of fencing methods, and is responsible for trying each one in turn while logging informative output.

The fencing methods are configured as a carriage-return separated list. Each line in the list is of the form:

com.example.foo.MyMethod(arg string) or com.example.foo.MyMethod The class provided must implement the FenceMethod interface. The fencing methods that ship with Hadoop may also be referred to by shortened names:

• shell(/path/to/some/script.sh args...) (see ShellCommandFencer)
• sshfence(...) (see SshFenceByTcpPort)
• powershell(...) (see PowerShellFencer)

Method Summary

Modifier and Type	Method	Description
static NodeFencer	create(Configuration conf, java.lang.String confKey)
boolean	fence(HAServiceTarget fromSvc)
boolean	fence(HAServiceTarget fromSvc, HAServiceTarget toSvc)

Methods inherited from class java.lang.Object

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

Method Detail

create

public static NodeFencer create(Configuration conf,
                                java.lang.String confKey)
                         throws BadFencingConfigurationException

Throws:

BadFencingConfigurationException

fence

public boolean fence(HAServiceTarget fromSvc)

fence

public boolean fence(HAServiceTarget fromSvc,
                     HAServiceTarget toSvc)