org.apache.hadoop.hbase.chaos.monkies

Class ChaosMonkey

java.lang.Object

org.apache.hadoop.hbase.chaos.monkies.ChaosMonkey

All Implemented Interfaces:

Stoppable

Direct Known Subclasses:

CalmChaosMonkey, PolicyBasedChaosMonkey

public abstract class ChaosMonkey
extends java.lang.Object
implements Stoppable

A utility to injects faults in a running cluster.

ChaosMonkey defines Action's and Policy's. Actions are sequences of events, like - Select a random server to kill - Sleep for 5 sec - Start the server on the same host Actions can also be complex events, like rolling restart of all of the servers.

Policies on the other hand are responsible for executing the actions based on a strategy. The default policy is to execute a random action every minute based on predefined action weights. ChaosMonkey executes predefined named policies until it is stopped. More than one policy can be active at any time.

Chaos monkey can be run from the command line, or can be invoked from integration tests. See IntegrationTestIngest or other integration tests that use chaos monkey for code examples.

ChaosMonkey class is indeed inspired by the Netflix's same-named tool: http://techblog.netflix.com/2012/07/chaos-monkey-released-into-wild.html

Constructor Summary

Constructors

Constructor and Description
ChaosMonkey()

Method Summary

Modifier and Type	Method and Description
abstract boolean	isDestructive() Returns whether the CM does destructive actions (killing servers) so that a cluster restore is needed after CM is stopped.
abstract boolean	isStopped()
abstract void	start()
abstract void	stop(java.lang.String why) Stop this service.
abstract void	waitForStop()

Methods inherited from class java.lang.Object

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

Constructor Detail

ChaosMonkey

public ChaosMonkey()

Method Detail

start

public abstract void start()
                    throws java.lang.Exception

Throws:

java.lang.Exception

stop

public abstract void stop(java.lang.String why)

Description copied from interface: Stoppable

Stop this service.

Specified by:

stop in interface Stoppable

Parameters:

why - Why we're stopping.

isStopped

public abstract boolean isStopped()

Specified by:

isStopped in interface Stoppable

Returns:

True if Stoppable.stop(String) has been closed.

waitForStop

public abstract void waitForStop()
                          throws java.lang.InterruptedException

Throws:

java.lang.InterruptedException

isDestructive

public abstract boolean isDestructive()

Returns whether the CM does destructive actions (killing servers) so that a cluster restore is needed after CM is stopped. Otherwise cluster will be left as it is