SAP are discontinuing Dual-Stack Installations - Could this benefit you?

You may, or may not, be aware that SAP are discontinuing the use of dual-stack SAP instances for future releases.  What this means is, as of 7.4, you won’t be able to have your ABAP and Java stacks share a common SID (System ID).  Dual-stack systems also resided on the same database and have the same startup framework (i.e. starting or stopping at the same time).

If you are planning to upgrade to a newer NetWeaver 7.4 based release, you will have to include a stack split into your upgrade path.

The origin of the dual-stack instance was one of a desire to offer a package with a reduced TCO, against having two separate stacks.  Today, however, these cost savings can be achieved in a more flexible way.  Databases can usually be shared with ‘multi-tenant’ options, if required.  The cost of patching a dual-stack system was in reality, almost exactly the same as patching separate ABAP and Java stacks.  There was also no tight integration between the two stacks, with both connecting via JCos and RFCs anyway, so splitting them will have little impact on applications.

Depending on your landscape, you may even be able to remove one of the stacks – providing immediate savings to the TCO of your landscape.  For example:  If you use SAP PI, you may be able to leverage the ‘Java only’ PI version called Advanced adapter Engine Extended (AEX).  This runs on a single Java stack and provides most of the functionality of the dual stack equivalent.  With only one stack to support, patching effort is greatly reduced, less memory is required on the host server, and also the complexity of interfacing is also diminished.

Having said that, there is one exception to the discontinuation of dual stack support, and that is PI:  SAP recommend moving to AEX, however, for more complex implementations which require the full dual-stack PI functionality, this will be supported in NetWeaver 7.4.

Currently, the newest Solution Manager 7.1 runs on NetWeaver 7.01, and is dual-stack only.  Solution Manager 7.2, which is set for ramp-up release later this year, will run on NetWeaver 7.40, and will not be dual-stack.  The stack split will be part of the upgrade procedure and will be performed automatically.  The ‘Mainstream Maintenance’ of Solution Manager 7.1 finishes at the end of 2017, which is the same as the NetWeaver 7.0 -> 7.03 releases.

In order so implement your splitting strategy, SAP provide the dual-stack split tool.  This tool is quite similar to a ‘System Copy’ with SWPM (SoftWare Provisioning Manager), however the tool removes the ‘old’ Java instance.  The tool then allows you to use the same DB as before, if there is a ‘multi-tenant’ option, or to copy to a separate DB.

SAP are not releasing NetWeaver for SAP HANA with dual-stack support.  There is however a version of SAP Solution Manager 7.1, powered by SAP HANA.

With dual-stack systems eventually phased out of your landscape, this should allow you more flexibility with what to do with your systems and servers: 

  • You can spread your landscape out over less powerful hardware, or combine systems on one host as before.
  • You will have more flexibility around when to patch and upgrade each stack.
  • You can have one Java Enterprise Portal without federating, or split out applications and federate your portal network.
  • You will ensure support of your ABAP systems beyond 2017.

With SAP’s strategy to discontinue dual-stack SAP systems, you will actually have more choice with what to do with your landscape, and if you are smart this will lead to some cost savings along the way.

For more information about the topics covered in our blog, contact Absoft today via: info@absoft.co.uk or T: +44 1224 707088 to speak with our SAP consultants.

by Ross Hamilton, SAP Consultant