Credentials for token delegation
A secure cluster requires the Oozie actions to be authenticated; typically using Kerberos. However, due to the way that Oozie runs actions, Kerberos credentials are not available to them. Some actions require communication to an external service like HCatalog, HBase, and Hive or a secure file system like Amazon S3. For these situations, Oozie has to use its Kerberos credentials to obtain delegation tokens which allows Oozie to access the external service or file system.
For information about Action Authentication, see Apache Oozie documentation.