ClusterId read in ZooKeeper is null.

Re-running the program after fixing issue 1 will result in the following error in the log file (Oddly logged at INFO level)

13/12/11 09:45:33 INFO zookeeper.ZooKeeper: Initiating client connection, connectString=localhost:2181 sessionTimeout=90000 watcher=hconnection-0x207f5580

13/12/11 09:45:33 INFO zookeeper.RecoverableZooKeeper: Process identifier=hconnection-0x207f5580 connecting to ZooKeeper ensemble=localhost:2181
13/12/11 09:45:33 INFO zookeeper.ClientCnxn: Opening socket connection to server localhost.localdomain/127.0.0.1:2181. Will not attempt to authenticate using SASL (java.lang.SecurityException: Unable to locate a login configuration)
13/12/11 09:45:33 INFO zookeeper.ClientCnxn: Socket connection established to localhost.localdomain/127.0.0.1:2181, initiating session
13/12/11 09:45:33 INFO zookeeper.ClientCnxn: Session establishment complete on server localhost.localdomain/127.0.0.1:2181, sessionid = 0x142e28373f3000c, negotiated timeout = 40000
13/12/11 09:45:33 INFO client.ZooKeeperRegistry: ClusterId read in ZooKeeper is null

解决办法

The HBase clients will discover the running HBase cluster using the following two properties:

1. hbase.zookeeper.quorum: is used to connect to the zookeeper cluster
2. zookeeper.znode.parent. tells which znode keeps the data (and address for HMaster) for the cluster

The value of zookeeper.znode.parent in HBASE_CONF/hbase-site.xml is specified as /hbase-unsecure (see below) which is correct but for some reason (still trying to figure this out), the value being printed is /hbase. So currently I’ve overridden this programatically in the client program by adding the following line to the program

conf.set(“zookeeper.znode.parent”, “/hbase-unsecure”);