D8T021 is a "container" hot fix that contains "member" hot fixes which will update your SAS software components.
See "What is a container hot fix?" in the SAS Hot Fix FAQ for more information on container and member hot fixes.
A manifest listing the contents of each of the following "member" hot fixes is available:
D8P020 manifest for SAS Web Infrastructure Platform 9.4_M6
D8Q021 manifest for SAS Intelligence Platform Object Framework 9.4_M6
D8R020 manifest for SAS Configuration Manager 9.4_M6
D8S020 manifest for SAS Foundation Services 9.4_M6
G6K013 manifest for SAS Web Infrastructure Platform Scheduling Services 9.4_M6