When you perform a generate operation with an automatic receive, DCM uses the ccm_receive command to start the receive operation on the destination machine. This command starts a session, passes the arguments to the DCM receive operation, and then stops the session.
DCM performs automatic receives as the CM administrator user (on UNIX platforms this is always ccm_root). The engine process performs the receive operation, and the engine process runs as the CM administrator user. Moreover, the CM administrator user has the ccm_admin role; this role is required to change any non-modifiable objects when DCM loads the data.
Before selecting an Automatic Receive option in a destination database definition, be sure to read the topics that apply to the platforms you are using.