Question

I am running an hdfs instance in pseudo-distributed mode, and tried to make another hbase instance connected to it on the same server. Logs in hadoop are fine, but I constantly got the connection failure in hbase’ log

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2012-05-01 10:49:07,212 INFO org.apache.zookeeper.ClientCnxn: Opening socket connection to server localhost/127.0.0.1:2181
2012-05-01 10:49:07,213 WARN org.apache.zookeeper.ClientCnxn: Session 0x13708dc552d0001 for server null, unexpected error, closing socket connection and attempting reconnect
java.net.ConnectException: Connection refused
        at sun.nio.ch.SocketChannelImpl.checkConnect(Native Method)
        at sun.nio.ch.SocketChannelImpl.finishConnect(SocketChannelImpl.java:567)
        at org.apache.zookeeper.ClientCnxn$SendThread.run(ClientCnxn.java:1119)

2012-05-01 10:49:08,882 INFO org.apache.zookeeper.ClientCnxn: Opening socket connection to server localhost/127.0.0.1:2181
2012-05-01 10:49:08,882 WARN org.apache.zookeeper.ClientCnxn: Session 0x13708dc552d0001 for server null, unexpected error, closing socket connection and attempting reconnect
java.net.ConnectException: Connection refused
        at sun.nio.ch.SocketChannelImpl.checkConnect(Native Method)
        at sun.nio.ch.SocketChannelImpl.finishConnect(SocketChannelImpl.java:567)
        at org.apache.zookeeper.ClientCnxn$SendThread.run(ClientCnxn.java:1119)

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Configuration of core-site.xml@hadoop

<configuration>

<property>
    <name>fs.default.name</name>
    <value>hdfs://localhost:9000</value>
</property>

</configuration>

Configuration of hbase-site.xml@hbase

<configuration>
<property>
   <name>hbase.rootdir</name>
   <value>hdfs://localhost:9000/hbase</value>
</property>
<property>
   <name>dfs.replication</name>
   <value>1</value>
</property>
</configuration>

I also tried to replace localhost with the actual ip of the server, but got the same error.

Answer 1

I think Hbase cannot find the zookeeper quorum, you have to set the hbase.zookeeper.quorum property in hbase-site.xml. Also check if classpath is set properly or not, check this doc out http://hbase.apache.org/apidocs/org/apache/hadoop/hbase/mapreduce/package-summary.html#classpath