問題：我用eclipse(Mar.2 Release(4.5.2))連線hadoop2.5.1時報錯：Error：Call From roo/10.30.12.xxx to hostname1:9000 failed on connection exception:java.net.ConnectException:Connection refused:no further information;...如下圖所示：

    出現原因：hdfs-site.xml中配置的DFS Master的埠號和eclipse連線hdfs的埠號不同。hdfs-site.xml的配置如下：

<configuration>
<property>
  <name>dfs.nameservices</name>
  <value>mycluster</value>
</property>
<property>
  <name>dfs.ha.namenodes.mycluster</name>
  <value>nn1,nn2</value>
</property>
<property>
  <name><span style="color:#ff0000;">dfs.namenode.rpc-address.mycluster.nn1</span></name>
  <value><span style="color:#ff0000;">lida1:8020</span></value>
</property>
<property>
  <name>dfs.namenode.rpc-address.mycluster.nn2</name>
  <value>lida2:8020</value>
</property>
<property>
  <name>dfs.namenode.http-address.mycluster.nn1</name>
  <value>lida1:50070</value>
</property>
<property>
  <name>dfs.namenode.http-address.mycluster.nn2</name>
  <value>lida2:50070</value>
</property>
<property>
  <name>dfs.namenode.shared.edits.dir</name>
  <value>qjournal://lida2:8485;lida3:8485;lida4:8485/mycluster</value>
</property>
<property>
  <name>dfs.client.failover.proxy.provider.mycluster</name>
  <value>org.apache.hadoop.hdfs.server.namenode.ha.ConfiguredFailoverProxyProvider</value>
</property>
<property>
  <name>dfs.ha.fencing.methods</name>
  <value>sshfence</value>
</property>
<property>
  <name>dfs.ha.automatic-failover.enabled</name>
  <value>true</value>
</property>
<property>
  <name>dfs.permissions</name>
  <value>false</value>
</property>
</configuration>
 

    解決辦法：修改eclipse連線hdfs的埠號即可。如下圖所示：

修改完埠後，重啟eclipse，然後再開啟DFS locations，就不報上面的錯了。