我是hadoop开发的新手，我正在尝试在hadoop2.4.1上安装一个多节点集群。然而，我正在经历一些问题。当我尝试执行一个示例（wordcount或pi）时，执行在

INFO mapreduce.Job: Running job: job_1412689235580_0001

通过分析日志，我在resourcemanager日志中得到一个重复的错误：

2014-10-07 15:56:40,978 ERROR org.apache.hadoop.yarn.server.resourcemanager.scheduler.SchedulerApplicationAttempt: Error trying to assign container token and NM token to an allocated container container_1412689235580_0001_01_000001
java.lang.IllegalArgumentException: java.net.UnknownHostException: federica-VirtualBox
at org.apache.hadoop.security.SecurityUtil.buildTokenService(SecurityUtil.java:377)
at org.apache.hadoop.yarn.server.utils.BuilderUtils.newContainerToken(BuilderUtils.java:248)
at org.apache.hadoop.yarn.server.resourcemanager.security.RMContainerTokenSecretManager.createContainerToken(RMContainerTokenSecretManager.java:195)
at org.apache.hadoop.yarn.server.resourcemanager.scheduler.SchedulerApplicationAttempt.pullNewlyAllocatedContainersAndNMTokens(SchedulerApplicationAttempt.java:379)
at org.apache.hadoop.yarn.server.resourcemanager.scheduler.common.fica.FiCaSchedulerApp.getAllocation(FiCaSchedulerApp.java:240)
at org.apache.hadoop.yarn.server.resourcemanager.scheduler.capacity.CapacityScheduler.allocate(CapacityScheduler.java:716)
at org.apache.hadoop.yarn.server.resourcemanager.rmapp.attempt.RMAppAttemptImpl$AMContainerAllocatedTransition.transition(RMAppAttemptImpl.java:821)
at org.apache.hadoop.yarn.server.resourcemanager.rmapp.attempt.RMAppAttemptImpl$AMContainerAllocatedTransition.transition(RMAppAttemptImpl.java:814)
at org.apache.hadoop.yarn.state.StateMachineFactory$MultipleInternalArc.doTransition(StateMachineFactory.java:385)
at org.apache.hadoop.yarn.state.StateMachineFactory.doTransition(StateMachineFactory.java:302)
at org.apache.hadoop.yarn.state.StateMachineFactory.access$300(StateMachineFactory.java:46)
at org.apache.hadoop.yarn.state.StateMachineFactory$InternalStateMachine.doTransition(StateMachineFactory.java:448)
at org.apache.hadoop.yarn.server.resourcemanager.rmapp.attempt.RMAppAttemptImpl.handle(RMAppAttemptImpl.java:652)
at org.apache.hadoop.yarn.server.resourcemanager.rmapp.attempt.RMAppAttemptImpl.handle(RMAppAttemptImpl.java:106)
at org.apache.hadoop.yarn.server.resourcemanager.ResourceManager$ApplicationAttemptEventDispatcher.handle(ResourceManager.java:753)
at org.apache.hadoop.yarn.server.resourcemanager.ResourceManager$ApplicationAttemptEventDispatcher.handle(ResourceManager.java:734)
at org.apache.hadoop.yarn.event.AsyncDispatcher.dispatch(AsyncDispatcher.java:173)
at org.apache.hadoop.yarn.event.AsyncDispatcher$1.run(AsyncDispatcher.java:106)
at java.lang.Thread.run(Thread.java:745)
Caused by: java.net.UnknownHostException: federica-VirtualBox
... 19 more

有人知道这是什么意思吗？我该怎么解决？谢谢
戴维德