ZooKeeper exists failed after 3 retries

Question

I am running Hadoop-1.2.1 and HBase-0.94.11 in a pseudo-distributed mode.

Due to power failure Hadoop and HBase set up went down.Next time when I restarted my machine and the pseudo-distribution set up, HBase stopped working with the following errors on HBase shell:

13/11/27 13:53:27 ERROR zookeeper.RecoverableZooKeeper: ZooKeeper exists failed after 3 retries
13/11/27 13:53:27 WARN zookeeper.ZKUtil: hconnection Unable to set watcher on znode (/hbase/hbaseid)
org.apache.zookeeper.KeeperException$ConnectionLossException: KeeperErrorCode = ConnectionLoss for /hbase/hbaseid
    at org.apache.zookeeper.KeeperException.create(KeeperException.java:99)
    at org.apache.zookeeper.KeeperException.create(KeeperException.java:51)
    at org.apache.zookeeper.ZooKeeper.exists(ZooKeeper.java:1041)
    at org.apache.hadoop.hbase.zookeeper.RecoverableZooKeeper.exists(RecoverableZooKeeper.java:172)
    at org.apache.hadoop.hbase.zookeeper.ZKUtil.checkExists(ZKUtil.java:450)
    at org.apache.hadoop.hbase.zookeeper.ClusterId.readClusterIdZNode(ClusterId.java:61)
    at org.apache.hadoop.hbase.zookeeper.ClusterId.getId(ClusterId.java:50)
    at org.apache.hadoop.hbase.zookeeper.ClusterId.hasId(ClusterId.java:44)
    at org.apache.hadoop.hbase.client.HConnectionManager$HConnectionImplementation.ensureZookeeperTrackers(HConnectionManager.java:720)
    at org.apache.hadoop.hbase.client.HConnectionManager$HConnectionImplementation.getMaster(HConnectionManager.java:789)
    at org.apache.hadoop.hbase.client.HBaseAdmin.<init>(HBaseAdmin.java:129)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
    at java.lang.reflect.Constructor.newInstance(Constructor.java:526)

Following are the processes :

hduser@user-ubuntu:~$ jps
16914 NameNode
19955 Jps
29460 Main
17728 TaskTracker
19776 HMaster
17490 JobTracker
17392 SecondaryNameNode

Answer 1

Are you sure your Zookeeper process is running (your jps listing doesn't show an entry for QuorumPeerMain)? The jps stack may not show all java processes running - try using a ps axww | grep QuorumPeerMain.

If your zookeeper refuses to start, check its logs to see if there are some stack trace clues