Difference between ABAP Central Instance before and after SAP Netweaver 7.3

 

Introduction

In this blog, you will learn about difference ABAP Central instance structures and services before and after SAP Netweaver 7.3 release. this knowledge should be fit for Administrators who daily either deploy system (newly fresh installation) or manage an existing system.

OK, let me start with a simpler approach and started with an older SAP version first. As the Administrator team very often read SAP Installation guides however most of them do not understand what documents explain it. Some of them just do like often without analyzing what new features or updates from SAP. This happened when as new sap technical consultant whom has no experience before.

Terminology:

PAS    : Primary Application Server

ASCS : ABAP Central Services

ABAP Central Instance before SAP Netweaver 7.3 structure

Central Instance includes these main parts :

• ABAP Dispatcher & Work Process (DIA,BTC,UPD,ENQ,SPOOL)
• Gateway Service
• ICM (Internet Communication Manager) Service
• IGS (Internet Graphic Server)
• Message Server

Older SAP version includes 3 main profile :

• Default Profile,

Default profile has naming convention DEFAULT.PFL which contains basic information of SAP system

• Start Profile

Start profile has naming convention START_DVEBMGSXX_<HOSTNAME> which contains parameters for starting above services

• Instance Profile

Instance profile has naming conventioni <SID>_DVEBMGSXX_<HOSTNAME> which contains parameters regarding for tune purpose

 ABAP Central Instance as of SAP Netweaver 7.3

For newly installed SAP system has changed totally, from number of profile used, services splitted and also created new one ASCS Instance even if you install SAP system on single host (standard deployment). The benefit separated ASCS instance is for High-Avaliability purpose especially for reduce SPOF part. For advanced configuration you can split-off gateway from central instance and integrated with ASCS instance for increase High-Avaliability.

ASCS  Instance has been split off from Central Instance. SAP tools creates PAS Instance and ASCS Instance, this methodology actually has been standard for Java Stack (System) and now also standard for ABAP Stack.

The Primary Application Server (PAS) now includes:

• ABAP Dispatcher & Work Process (DIA,BTC,UPD,SPOOL)
• Gateway Service
• ICM (Internet Communication Manager) Service
• IGS (Internet Graphic Server)

The ABAP Central Services Instances (ASCS) now includes:

• Message Server
• Standalone Enqueue Server

Standalone enqueue server was Enqueue work process

Newest SAP version includes 3 main profiles:

• Default Profile,

Default profile has naming convention DEFAULT.PFL which contains basic information of SAP system

• ASCS Profile

Start profile has naming convention <SID>_ASCSXX_<HOSTNAME> which contains parameters for starting Message Server and Standalone Enqueue Server.

• PAS Profile

Instance profile has naming convention <SID>_DXX_<HOSTNAME> which contains parameters regarding for tune purpose as well as for starting ABAP dispatcher & Work Process, Gateway Server, IGS, ICM

 Conclusion:

You can distinguish which old SAP version and new SAP version by instance, services, and profile. so that easier to analyze when you have some issues.