hadoop2.6.0 nodemanager启动后过一段时间就自动关闭

hadoop2.6.0集群启动后，在slave节点上jps能够看到nodemanager进程，但是过一会nodemanager进程就不见了．查看日志发现是因为配置错误导致的，更改后所有的配置文件内容如下：(更改配置文件后，要删除之前配置文件里设置的相关目录里面所有的内容后重新format，再start-all)

core-site.xml

<configuration>  
    <property>  
        <name>fs.defaultFS</name>  
        <value>hdfs://master:9000</value>  
    </property>
<property>  
        <name>io.file.buffer.size</name>  
        <value>131072</value>  
    </property>  
    <property>  
        <name>hadoop.tmp.dir</name>  
        <value>file:/home/hadoop/hdfs/hadooptmp</value>  
    </property>  
</configuration> 

hdfs-site.xml

<configuration>  
    <property>  
        <name>dfs.replication</name>  
        <value>3</value>  
    </property>

   <property>
     <name>dfs.support.append</name>
     <value>true</value>
   </property>

    <property>  
        <name>dfs.namenode.name.dir</name>  
        <value>file:/home/hadoop/hdfs/namenode</value>  
    </property>  
  
    <property>
        <name>dfs.blocksize</name>  
        <value>1048576</value>  
    </property>  

 <property>  
        <name>file:dfs.datanode.data.dir</name>  
        <value>/home/hadoop/hdfs/datanode</value>  
    </property>

<property>  
        <name>dfs.webhdfs.enabled</name>  
        <value>true</value>  
    </property>

</configuration>

mapred-site.xml

<configuration>
    <property>
        <name>mapreduce.framework.name</name>
        <value>yarn</value>
    </property>


    <property>
        <name>mapreduce.jobhistory.address</name>
        <value>master:10020</value>
    </property>

    <property>
        <name>mapreduce.jobhistory.webapp.address</name>
        <value>master:19888</value>
    </property>

    <property>
        <name>mapreduce.tasktracker.map.tasks.maximum</name>
        <value>10</value>
    </property>

    <property>
        <name>mapreduce.tasktracker.reduce.tasks.maximum</name>
        <value>4</value>
    </property>

</configuration>

yarn-site.xml

<configuration>

<!-- Site specific YARN configuration properties -->
    <property>
        <name>yarn.nodemanager.aux-services</name>
        <value>mapreduce_shuffle</value>
    </property>

    <property>
        <name>yarn.nodemanager.aux-services.mapreduce.shuffle.class</name>
        <value>org.apache.hadoop.mapred.ShuffleHandler</value>
    </property>

    <property>
        <name>yarn.resourcemanager.admin.address</name>
        <value>master:8033</value>
    </property>

    <property>
        <name>yarn.resourcemanager.address</name>
        <value>master:8032</value>
    </property>

    <property>
        <name>yarn.resourcemanager.resource-tracker.address</name>
        <value>master:8031</value>
    </property>

    <property>
        <name>yarn.resourcemanager.scheduler.address</name>
        <value>master:8030</value>
    </property>
</configuration>