The Hadoop Application Timeline Server collects basic information about completed application processes. The Timeline Server also provides information about completed and running YARN applications.
The Grid Manager starts the Application Timeline Server in the Yarn configuration by default.
The Blaze engine uses the Application Timeline Server to store the Blaze Job Monitor status. On Hadoop distributions where the Timeline Server is not enabled by default, the Grid Manager attempts to start the Application Timeline Server process on the current node.
If you do not enable the Application Timeline Server on secured Kerberos clusters, the Grid Manager attempts to start the Application Timeline Server process in HTTP mode.