The Data Integration Service uses its credentials to impersonate the user accounts designated in the Hadoop connection to connect to the Hadoop cluster or to start the Blaze engine.

When the Data Integration Service impersonates a user account to submit a mapping, the mapping can only access Hadoop resources that the impersonated user has permissions on. Without user impersonation, the Data Integration Service uses its credentials to submit a mapping to the Hadoop cluster. Restricted Hadoop resources might be accessible.

When the Data Integration service impersonates a user account to start the Blaze engine, the Blaze engine has the privileges and permissions of the user account used to start it.