DAS: Core Concepts
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DAS architecture

DAS cluster agent comprises of a DAS Webapp and an Event Processor. These components are installed on the Ambari cluster to use with DAS.

Following is a block diagram showing the various components in a typical DAS deployment:

The DAS Webapp serves the DAS UI, and it should be on a machine that is accessible to your end users, or you should have a proxy setup to access the DAS UI.