Impala cannot find com.mysql.jdbc.Driver

Question

I'm trying to set up Cloudera Impala with CDH4 in pseudo distributed mode on Red Hat 5. I have Hive using JDBC to connect to a MySQL metastore, but I'm having trouble setting up Impala with JDBC. I've been following the instructions found here: http://www.cloudera.com/content/cloudera-content/cloudera-docs/Impala/latest/Installing-and-Using-Impala/ciiu_impala_jdbc.html

I've extracted the JARs to a directory and included that directory in $CLASSPATH. I've also included /usr/lib/hive/lib in $CLASSPATH, which has mysql-connector-java-5.1.25-bin.jar.

In both my Hive and Impala conf directories, I have hive-site.xml including the following properties:

<property>
    <name>javax.jdo.option.ConnectionURL</name>
    <value>jdbc:mysql://localhost/metastore</value>
</property>

<property>
    <name>javax.jdo.option.ConnectionDriverName</name>
    <value>com.mysql.jdbc.Driver</value>
</property>

<property>
    <name>javax.jdo.option.ConnectionUserName</name>
    <value>hiveuser</value>
</property>

<property>
    <name>javax.jdo.option.ConnectionPassword</name>
    <value>password</value>
</property>

<property>
    <name>datanucleus.autoCreateSchema</name>
    <value>false</value>
</property>

<property>
    <name>datanucleus.fixedDatastore</name>
    <value>true</value>
</property>

But when I run sudo service impala-server restart, the server log has this error:

ERROR common.MetaStoreClientPool: Error initializing Hive Meta Store client
javax.jdo.JDOFatalInternalException: Error creating transactional connection factory

Which it says is cause by this:

Caused by: org.datanucleus.store.rdbms.datasource.DatastoreDriverNotFoundException: The specified datastore driver ("com.mysql.jdbc.Driver") was not found in the CLASSPATH. Please check your CLASSPATH specification, and the name of the driver.
    at org.datanucleus.store.rdbms.datasource.dbcp.DBCPDataSourceFactory.makePooledDataSource(DBCPDataSourceFactory.java:80)
    at org.datanucleus.store.rdbms.ConnectionFactoryImpl.initDataSourceTx(ConnectionFactoryImpl.java:144)
    ... 57 more

Is there any step I'm missing to configure Impala with JDBC?

Answer 1

I fixed this by copying mysql-connector-java-5.1.25-bin.jar to /var/lib/impala - the startup script was telling the classpath to look here for the connector jar for some reason.