An SAP system is dual-stack, if it contains both SAP NetWeaver Application Server ABAP and Java with one common SAP system ID (SAPSID), one common start-up framework, and one common database.
Advantages of Dual-stack system
- Save Hardware cost for DB and Application as Java and ABAP part are installed on same physical machine
- Software Life Cycle management process was same i.e. ABAP and JAVA part is treated as a single UNIT
- Reduce Operation Cost
Disadvantages of Dual-stack system
- The tight coupling between the ABAP and Java stacks became more and more an innovation hurdle
- Downtime of one stack in a dual-stack system affected the whole system
- Dual-stack systems could not be scaled independently
Going forward SAP is recommending Single stack installation of ABAP and JAVA stack & supporting it with Dual-stack Split tool & with latest Business suit package. As of NW 7.4 no dual-stack installation will be supported.
Only dual-stack systems which will be available are SAP Solution Manager & SAP PI. SAP PI also available with Single JAVA stack version with NW 7.4 which covers 95% of a classical PI environment & capabilities.
For more details please refer SAP Roadmap