我可以启动namenode和secondary namenode，但无法启动jobtracker和tasktracker。
当我查看日志时，它显示类似这样的内容

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2013-05-30 07:27:50,962 FATAL org.apache.hadoop.conf.Configuration: bad conf file: top-level element not <configuration>
2013-05-30 07:27:50,963 WARN org.apache.hadoop.conf.Configuration: bad conf file: element not <property>
2013-05-30 07:27:50,963 WARN org.apache.hadoop.conf.Configuration: bad conf file: element not <property>
2013-05-30 07:27:50,963 WARN org.apache.hadoop.conf.Configuration: bad conf file: element not <property>
2013-05-30 07:27:51,204 INFO org.apache.hadoop.metrics2.impl.MetricsConfig: loaded properties from hadoop-metrics2.properties
2013-05-30 07:27:51,360 INFO org.apache.hadoop.metrics2.impl.MetricsSourceAdapter: MBean for source MetricsSystem,sub=Stats registered.
2013-05-30 07:27:51,365 INFO org.apache.hadoop.metrics2.impl.MetricsSystemImpl: Scheduled snapshot period at 10 second(s).
2013-05-30 07:27:51,365 INFO org.apache.hadoop.metrics2.impl.MetricsSystemImpl: TaskTracker metrics system started
2013-05-30 07:27:51,440 INFO org.apache.hadoop.util.NativeCodeLoader: Loaded the native-hadoop library
2013-05-30 07:27:51,587 FATAL org.apache.hadoop.conf.Configuration: bad conf file: top-level element not <configuration>
2013-05-30 07:27:51,587 WARN org.apache.hadoop.conf.Configuration: bad conf file: element not <property>
2013-05-30 07:27:51,588 WARN org.apache.hadoop.conf.Configuration: bad conf file: element not <property>
2013-05-30 07:27:51,588 WARN org.apache.hadoop.conf.Configuration: bad conf file: element not <property>
2013-05-30 07:27:51,594 INFO org.apache.hadoop.metrics2.impl.MetricsSourceAdapter: MBean for source ugi registered.
2013-05-30 07:27:51,603 WARN org.apache.hadoop.metrics2.impl.MetricsSystemImpl: Source name ugi already exists!
2013-05-30 07:27:51,773 FATAL org.apache.hadoop.conf.Configuration: bad conf file: top-level element not <configuration>
2013-05-30 07:27:51,773 WARN org.apache.hadoop.conf.Configuration: bad conf file: element not <property>
2013-05-30 07:27:51,773 WARN org.apache.hadoop.conf.Configuration: bad conf file: element not <property>
2013-05-30 07:27:51,773 WARN org.apache.hadoop.conf.Configuration: bad conf file: element not <property>
2013-05-30 07:27:51,799 ERROR org.apache.hadoop.mapred.TaskTracker: Can not start task tracker because java.lang.IllegalArgumentException: Does not contain a valid host:port authority: local
    at org.apache.hadoop.net.NetUtils.createSocketAddr(NetUtils.java:164)
    at org.apache.hadoop.net.NetUtils.createSocketAddr(NetUtils.java:130)
    at org.apache.hadoop.mapred.JobTracker.getAddress(JobTracker.java:2121)
    at org.apache.hadoop.mapred.TaskTracker.<init>(TaskTracker.java:1540)
    at org.apache.hadoop.mapred.TaskTracker.main(TaskTracker.java:3937)

2013-05-30 07:27:51,805 INFO org.apache.hadoop.mapred.TaskTracker: SHUTDOWN_MSG: 
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SHUTDOWN_MSG: Shutting down TaskTracker at ubuntu2/192.168.44.131

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