Apache Sentry is a modular security system that enables administrators to control access to data and metadata stored on an Apache Hadoop cluster by defining user roles and permissions. The driver works transparently with Sentry and does not require further configuration. To use Sentry, Kerberos authentication must be enabled, and a Kerberos logon must be provided at connection.
Note: When establishing a connection, the driver attempts to set the user's default database to be used for the session. In environments using Sentry, the user must be granted access to this database; otherwise, the connection will fail.

For more information, refer to the Cloudera Impala documentation at http://cloudera.com/content/cloudera/en/documentation.html.