Considering an SAP S/4HANA System Conversion and Preparing for Implementation

SAP S/4HANA was introduced back in 2015 as a completely rebuilt version of the SAP Business Suite, running on the SAP HANA database.


With its revamped data model, SAP S/4HANA is its own product, rather than a successor to SAP ERP. This means companies will need to do more than just upgrade their legacy system in order to use SAP S/4HANA.


SAP has announced a 2027 deadline for companies to move to SAP S/4HANA (with an option for extended SAP ERP maintenance through 2030 for those who are still transitioning by the cutoff date). By then, companies on SAP ERP who plan to continue with SAP will need to make the switch to SAP S/4HANA. There are multiple ways to achieve this, including brownfield, greenfield, and hybrid implementations. Determining which approach works best is based on the specific needs and goals of an organization. In this blog post, we’ll explore the brownfield approach, provide insight on what it means for your company, and discuss what to consider when planning a migration.


Brownfield Implementation

A system conversion, often referred to as a “brownfield” approach, is an implementation method that is fulfilled by taking an existing SAP ERP system and converting it to SAP S/4HANA. This means that an organization’s existing master and transactional data, custom development objects, and system customizations will be migrated to their new SAP S/4HANA system once the conversion is completed. This is opposed to a new implementation (or greenfield implementation), which is an alternative approach companies choose when they decide to build their SAP S/4HANA system from scratch; or a hybrid implementation, which combines aspects of both greenfield and brownfield, and varies from company to company.


A conversion can be completed in one step in most cases; however, if you have a system older than SAP ERP 6.0, you’ll be required to perform a two-phase process. In the two-phase scenario, the first step is to upgrade your system to a supported source release. Then, you’re able to convert it to SAP S/4HANA.


It's important to understand that not every system can be converted to SAP S/4HANA as-is, since there are a number of prerequisites that must be met. For example, add-ons and all business functions need to be compatible with the new system. If they are not compatible, you must remove any incompatibilities before converting or choose the greenfield approach.


Brownfield Conversion Pros

A brownfield approach is generally less costly since you’re taking existing data and transferring it to another location, eliminating the need to rebuild your landscape. By incorporating legacy data into your SAP S/4HANA system, you don’t have to take the time to redesign certain processes. Your master data automatically migrates over to the new system, relieving you of having to extract and load it as you would if you were starting a brand-new project (the greenfield option). Another advantage of a brownfield approach is that the conversion is an opportunity to clean and remove old custom code, or reduce the data footprint via data archiving.



Brownfield Conversion Cons

One issue many organizations can’t ignore when it comes to a brownfield project is the time it takes to complete the migration. As mentioned above, companies can benefit from the data cleanup a conversion provides, but it comes at a timely cost. Also, the conversion has to be done all at once, which means all work will be put to a halt. How much time the conversion will take will vary based on each organization’s landscape—the larger and more complex a landscape, the more time the conversion will require. A migration also requires a bit of rework and reorganization to your new system.


SAP S/4HANA System Conversion Guide

It can be very overwhelming to execute a system conversion, especially if you’ve never done one before. We published SAP S/4HANA System Conversion Guide to help companies and consultants plan and perform their migrations.


You’ll start with an introduction to SAP S/4HANA, explore the concept of simplification, and learn about the recommended conversion methodology. Then, dive into SAP S/4HANA architecture, conversion tools, strategy, and project planning.


The conversion process is looked at more closely when you move further into the book. Several components and tools that are required to perform the conversion are discussed, along with an explanation of how to obtain them.


Next, learn the technical side of the conversion from SAP ERP to SAP S/4HANA by going through a complete conversion using the Software Update Manager (SUM) with the Database Migration Option (DMO). You’ll also review the post-processing activities that follow the conversion.


Understand how to perform the modification adjustment for Data Dictionary objects with Transaction SPDD and go through several adjustment operations. Then, take a look at the impact custom code has on your system and the necessary activities to perform a custom code migration.


Wrap up with a discussion about the obligatory conversion of customers and suppliers to business partners, and the activities that are needed for a functional conversion of the financials and accounting, credit management, trade finance, logistics, and sales and distribution lines of business.


Who Is This Book For?

This book is suitable for administrators and technical consultants preparing for or participating in an SAP S/4HANA system conversion. If you’re a developer working on converting code, a functional consultant working to adapt data and convert business processes, or a product manager in charge of keeping all the logistics of the conversion in check, you’ll also find this title beneficial.


About the Authors

Mark Mergaerts is a principal technical consultant at Expertum and has more than 20 years of SAP experience. His activities concentrate on system administration, database management, performance, upgrades, and platform and Unicode migrations. He has written four other books for SAP PRESS.


Bert Vanstechelman is partner of and principal technical consultant at Expertum, and the founder of Logos Consulting, now a part of Expertum. He has more than 20 years of SAP experience. Bert specializes in platform migrations, SAP installations, release upgrades, SAP Business Warehouse, SAP Supply Chain Management, SAP HANA, and OS/DB migrations. Bert is an advisor for SAP Professional Journal, an SAP Solution Manager Expert, and has written four other books for SAP PRESS.


How to Purchase

If you’re interested in purchasing SAP S/4HANA System Conversion Guide, follow this link and choose the format that works best for you: e-book, print edition, or bundle (both e-book and print).


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SAP S/4HANA System Conversion Guide
SAP S/4HANA System Conversion Guide

If you’re performing a brownfield migration from an existing SAP ERP system, this is the technical guide for you! From planning the project and preparing your system to adjusting custom code and executing the conversion, you’ll get step-by-step instructions for all stages of your implementation. Troubleshooting tips and extensive coverage of the functional conversion will help you ensure that all your data makes it to where it needs to be. The time to move to SAP S/4HANA is here!

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SAP PRESS is the world's leading SAP publisher, with books on ABAP, SAP S/4HANA, SAP CX, intelligent technologies, SAP Business Technology Platform, and more!