Connecting to Hbase Mapr using Java

Question

Hi I am running the hbase VMWare sandbox MapR-Sandbox-For-Hadoop-3.1.0_VM. I have made no changes to the sandbox. I can access the control panel via browser. On another linux VM I have eclipse and the hbase client installed. I have a java program where I want to create a hbase table but I cannot connect. Please help

As you can see below I get an ERROR

ERROR client.HConnectionManager$HConnectionImplementation: Check the value configured in 'zookeeper.znode.parent'. There could be a mismatch with the one configured in the master.

and then

timesorg.apache.hadoop.hbase.MasterNotRunningException: Retried 1 times

(see full stacktraace below).

My application uses

System.setProperty("java.library.path", "/opt/mapr/lib");
conf = HBaseConfiguration.create();  
conf.set("zookeeper.znode.parent", "/maprdemo");
conf.set("hbase.zookeeper.quorum", "16.49.150.79");
conf.set("hbase.zookeeper.property.clientPort", "5181");
conf.set("hbase.client.retries.number", "2");
admin = new HBaseAdmin(conf); 
System.out.println(admin.isMasterRunning());

POM includes

<dependency>
    <groupId>org.apache.hbase</groupId>
    <artifactId>hbase</artifactId>
    <version>0.94.13-mapr-1401-m7-3.1.0</version>
</dependency>

Stacktrace

14/06/09 15:28:11 INFO zookeeper.ClientCnxn: Opening socket connection to server mapr.sandbox.com/16.49.150.79:5181. Will attempt to SASL-authenticate using Login Context section 'Client_simple'
14/06/09 15:28:11 INFO zookeeper.ClientCnxn: Socket connection established to mapr.sandbox.com/16.49.150.79:5181, initiating session
14/06/09 15:28:11 INFO zookeeper.ClientCnxn: Session establishment complete on server mapr.sandbox.com/16.49.150.79:5181, sessionid = 0x146807e8acc0090, negotiated timeout = 40000
14/06/09 15:28:11 ERROR client.HConnectionManager$HConnectionImplementation: Check the value configured in 'zookeeper.znode.parent'. There could be a mismatch with the one configured in the master.
14/06/09 15:28:11 INFO client.HConnectionManager$HConnectionImplementation: Closed zookeeper sessionid=0x146807e8acc0090
14/06/09 15:28:11 INFO zookeeper.ZooKeeper: Session: 0x146807e8acc0090 closed
14/06/09 15:28:11 INFO zookeeper.ClientCnxn: EventThread shut down
Retried 1 timesorg.apache.hadoop.hbase.MasterNotRunningException: Retried 1 times
    at org.apache.hadoop.hbase.client.HBaseAdmin.connectWithConfiguration(HBaseAdmin.java:184)
    at org.apache.hadoop.hbase.client.HBaseAdmin$1.connect(HBaseAdmin.java:153)
    at org.apache.hadoop.hbase.client.HBaseAdmin.ensureConnectedToHBase(HBaseAdmin.java:272)
    at org.apache.hadoop.hbase.client.HBaseAdmin.ensureConnectedToHBase(HBaseAdmin.java:247)
    at org.apache.hadoop.hbase.client.HBaseAdmin.isMasterRunning(HBaseAdmin.java:439)
    at com.hp.spark.hbase.test.HBaseTest.testCreateSchema(HBaseTest.java:72)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:606)
    at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:47)
    at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
    at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:44)
    at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
    at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:26)
    at org.junit.internal.runners.statements.RunAfters.evaluate(RunAfters.java:27)
    at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:271)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:70)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:50)
    at org.junit.runners.ParentRunner$3.run(ParentRunner.java:238)
    at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:63)
    at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:236)
    at org.junit.runners.ParentRunner.access$000(ParentRunner.java:53)
    at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:229)
    at org.junit.runners.ParentRunner.run(ParentRunner.java:309)
    at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:50)
    at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:467)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:683)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:390)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:197)

score 2 · Accepted Answer · answered Jun 27 '14 at 14:19

Looks like you are attempting to access M7 mapr native tables ( which is a different implementation of the HBase APIs )

The zookeeper znodes are irrelevant in M7.So the lines below don't make a difference.

conf.set("zookeeper.znode.parent", "/maprdemo");
conf.set("hbase.zookeeper.quorum", "16.49.150.79");
conf.set("hbase.zookeeper.property.clientPort", "5181");

It also does not require the hbase master and region services to be running. So you won't find a master service running on the sandbox. It's installed on the node though.

maprcli node services -nodes `cat /opt/mapr/hostname` -hbmaster restart

You can manually start it and re run your application.

To clarify : If you want to just test master running, restart hbmaster using the command above and continue. If you want to test M7, try some direct access on the tables without starting the master. — Nabeel Moidu, Jun 27 '14 at 14:21

score 0 · Answer 2 · answered Sep 25 '17 at 18:17

You can change the way you access using the property
conf.set("mapr.hbase.default.db", );

You have to set the znode parent etc when you are using HBase as Nabeel suggested.

Please note that this is applicable to only binary tables of mapr tables. For JSON Mapr db tables, you OJAI APIs.

Connecting to Hbase Mapr using Java

2 Answers2