get “ERROR: Can't get master address from ZooKeeper; znode data == null” when using Hbase shell

Question

I installed Hadoop2.2.0 and Hbase0.98.0 and here is what I do :

$ ./bin/start-hbase.sh 

$ ./bin/hbase shell

2.0.0-p353 :001 > list

the

Answer 1

In my case with same error in running hbase - I did not include the zookeeper properties in the hbase-site.xml and still get the above error messages (as based in Apache hbase guide, only the two properites: rootdir, and distributed are essential).

I can also trace back my output of jps command that find out that indeed my Hregion server and Hmaster were not properly up and running.

After stop and start (like a reset), I did have these two up and running and can run hbase properly.

Answer 2

If you just want to run HBase without going into Zookeeper management for standalone HBase, then remove all the property blocks from hbase-site.xml except the property block named hbase.rootdir.

Now run /bin/start-hbase.sh. HBase comes with its own Zookeeper, which gets started when you run /bin/start-hbase.sh, which will suffice if you are trying to get around things for the first time. Later you can put distributed mode configurations for Zookeeper.

You only need to run /sbin/start-dfs.sh for running HBase since the value of hbase.rootdir is set to hdfs://127.0.0.1:9000/hbase in your hbase-site.xml. If you change it to some location on local the filesystem using file:///some_location_on_local_filesystem, then you don't even need to run /sbin/start-dfs.sh.

hdfs://127.0.0.1:9000/hbase says it's a place on HDFS and /sbin/start-dfs.sh starts namenode and datanode which provides underlying API to access the HDFS file system. For knowing about Yarn, please look at http://hadoop.apache.org/docs/r2.3.0/hadoop-yarn/hadoop-yarn-site/YARN.html.