You plan to implement an SAP S/4HANA system and you have already decided that a greenfield migration approach (start from scratch) is not the right choice for you. So you are wondering which steps you need to take to complete the conversion from your current SAP ECC system landscape to SAP S/4HANA (brownfield migration approach). This blog article guides you through the different steps that you need to complete during your SAP S/4HANA brownfield conversion.
The image below outlines the stages of an SAP S/4HANA conversion:
The conversion is divided into two phases: the preparation and the technical conversion phase. We will discuss each of the different steps per phase in more detail in the following paragraphs.
5 steps to prepare your brownfield migration to SAP S/4HANA
During the preparation phase, your current SAP ECC system will be enabled to carry out the migration to S/4HANA.
Project Planning for your own Brownfield Migration
But before the technical activities of a conversion project can begin, we recommend starting with a planning phase in order to specify the parameters (e.g. scope, schedule, budget, project organisation) and to make sure that the entire project team is on the same page in regard to the technical aspects and the procedure.
Afterwards, the steps to complete a brownfield project can commence.
Review the System Requirements
The first step is to review the system requirements:
- Is your system unicode-enabled?
- Is a Dual Stack Split required?
- Is a database update required?
Maintenance Planner (MP)
Subsequently, the MP, a tool provided by SAP, will check whether the installed components, add-ons, and business functions are compatible with S/4HANA. It also generates the download files that the Software Update Manager (SUM) will require for the migration at a later point.
If all checks were successful, the conversion to SAP S/4HANA will be permitted. If the MP does not locate a valid migration path (e.g. because an add-on is not certified for S/4HANA), the tool will prevent the migration from going ahead.
Simplification Item Check
The subsequent simplification item check identifies important steps that must be completed in order to allow the technical migration of the system and to ensure that business processes will continue to run after the SAP S/4HANA migration is complete. This includes certain plausibility checks (such as in asset accounting) that identify inconsistencies within the SAP system. A detailed log provides information on errors and possible solutions.
Migration of the Custom Code
The migration of the custom code includes the analysis of developments (Z programmes, enhancements, and modifications) and provides information on where the code is not compatible with the new data structures. At this point, it is recommended to prepare, as early as possible, a priority list of which adjustments are either absolutely necessary or optional.
Many of our customers work with custom developments that are no longer used. If this is the case, we recommend running an extensive analysis of the system using the ABAP Call Monitor (SCMON) and deleting obsolete coding or programmes that are no longer in use.
Furthermore, there are a number of cross-module tasks, such as the adjustment of authorisations for using FIORI, and module-specific tasks. For example, for the logistics processes within SAP, the customer master data and supplier master data need to be converted into Business Partners before the conversion takes place.
How to start your technical brownfield conversion to SAP S/4HANA
Software Update Manager (SUM)
Once you have completed all steps of the preparation phase, the data can be migrated using the SUM. If you do not already have a HANA database, implementing this will be the first step of the brownfield conversion phase. The new tools, applications and data structures will be installed afterwards. The last step is the actual migration, which converts the master data and transaction data into the new data model.
Once the migration was successful, the validation of the system will start, which will ultimately lead to your Go/No-Go decision for the Go-Live.
Next Technical Steps of your Brownfield Migration
Some subsequent post-processing steps will be necessary. The new data structure requires you to align your coding, and some customising of settings in Logistics and Accounting will be necessary.
Some of the steps mentioned before will have to be carried out multiple times over the duration of the project, depending on your scheduled number of test migrations.
If you would like to learn more about an SAP S/4HANA project, you are welcome to read our other blog posts concerning S/4HANA. If you have any questions, want more tips & tricks, or if you are uncertain whether a brownfield, greenfield or hybrid approach would be best for your business, just contact us. Via the link below you can request a web-meeting with one of our expert consultants.