What Is the Difference Between the Legacy Migration Workbench (LSMW) and the SAP S/4HANA Migration Cockpit?

FrankFinkbohner · ‎2024 Oct 07

What Is the Difference Between the Legacy Migration Workbench (LSMW) and the SAP S/4HANA Migration Cockpit?

Legacy Migration Workbench (LSMW)

The LSMW is a tool that was initially built for migration from SAP R/2 to SAP R/3. Then, as it was enhanced over the years, it came to be the data migration tool for SAP ERP. The user creates projects and subprojects. Within a subproject, the user creates a user-defined data migration object and selects a data migration method (BAPI (Business Application Programming Interfaces), IDoc (Intermediate Document), SAP program, batch input recording) to migrate the data. The target structure is either predefined (for SAP program), retrieved from the API (Application Programming Interface) structure (for IDoc, BAPI), or self-defined (for batch input recording).

The user needs to define the source structure themselves including fields and their length, description, and data types.
The source structure and source fields must then be assigned to the target structures and target fields and the complete value mapping must be done by the users themselves.
Next, the source data files must be defined and assigned to the structures, then the files need to be uploaded, and the data is converted into the target structures using the field and value mappings.

At the end, the user needs to trigger the upload. Depending on your data migration method, simulation is handled differently: it’s either provided in the method (SAP program) or, if possible, it must be implemented by the user (BAPI/IDocs), or it is not possible at all (batch input recording). The LSMW is completely file based and allows users to upload files with a self-defined data structure.

The LSMW can be called an all-in-one data migration object modeling and execution workbench.

Technically, the LSMW is a backend transaction with transaction code LSMW.

SAP S/4HANA Migration Cockpit

The migration cockpit is a data migration tool built in SAP S/4HANA Cloud Public Edition and SAP S/4HANA including SAP S/4HANA Cloud Private Edition to migrate master data and transactional data. The user creates a migration project, selects data migration objects that are predefined by SAP and assigns them to that project. Technically, the predefined migration object definition is copied to the project.

The migration cockpit supports two different data migration approaches:

Staging Tables: Data is stored in predefined temporary project- dependent staging tables that can be filled either directly on database level with the help of tools or with predefined migration template files in XML or CSV format. In the backend, the data migration is handled by the Migration Workbench (MWB).
Direct Transfer: Data from four different scenarios can be directly extracted from SAP ERP, AFS, CRM (Customer Relationship Management), eSPP, EWM (Extended Warehouse Management) and then migrated into the respective SAP S/4HANA system (SAP S/4HANA, or SAP S/4HANA Cloud Private Edition). For SAP S/4HANA Cloud Public Edition extraction from SAP ERP was released with 2402 (with 21 available migration objects). Here, the Posting Engine is the tool that handles the data migration in the backend.

Sender structure, target structure, structure mapping, field mapping, field and event rules are all predefined. After the source data is loaded into the staging tables or extracted from the SAP system, the user confirms the value mappings, then runs the simulation, and afterwards performs the data migration for the data migration objects.

Since the objects are predefined, the migration cockpit is a data migration execution tool. All predefined data migration objects also support simulation. You can additionally monitor the data migration runs. The migration cockpit includes also functionality to analyze the return messages of the data simulation/migration.

The migration cockpit was initially based on the Web Dynpro backend transaction LTMC with limited functionality. The LTMC was retired with SAP S/4HANA 2021 and got replaced by the new SAP Fiori based Migrate Your Data app with better usability and much more functionality.

In addition, SAP delivers the SAP S/4HANA migration object modeler (LTMOM) that customers can use to model their own custom data migration objects, to modify the pre-delivered copied data migration objects, or to adapt the selection criteria (Direct Transfer approach). The LTMOM enhances the migration cockpit with modelling capabilities like those in the LSMW.

The LTMOM is a backend transaction and available for SAP S/4HANA and SAP S/4HANA Cloud Private Edition with no restrictions.

In SAP S/4HANA Cloud Public Edition, the LTMOM is available as SAP Fiori app Model Your Migration Object (Harmonized UI (User Interface)) with limited functionality:

For a small number of migration objects, you can add other fields that are already available within the data migration API. Only fields for migration objects that were released by SAP with SAP Note 2999428 can be added.
You can adapt the extract selection criteria for the Direct Transfer approach.

The migration cockpit is neither designed to keep data in sync between different systems, nor to update existing data (for example, mass maintenance), nor to realize a continuous exchange or flow of data, nor to set up an integration scenario.

What Are the Main Differences Between LSMW and the Migration Cockpit?

Tool Definition

The LSMW is an all-in-one tool to create own migration objects and to run the data migration. The LSMW has no analyzing or monitoring capabilities. A simulation of the data migration is not foreseen and for some migration methods (batch input) is not even possible. Simulation must be implemented manually in case the API supports the simulation mode.

The SAP S/4HANA migration cockpit is split into two tools:

the migration cockpit to simulate, perform, monitor, and analyze a data migration run
the migration object modeler to modify existing and create user-defined data migration objects.

Supported Data Sources

The SAP S/4HANA migration cockpit and the LSMW support CSV files as data source. The migration cockpit also supports Microsoft Excel's specific XML Spreadsheet 2003 file format. The SAP S/4HANA migration cockpit approach Direct Transfer can even retrieve data directly from selected SAP source systems.

	Legacy System Migration Workbench	SAP S/4HANA Migration Cockpit
CSV files	X	X
XML files	-	X
Direct transfer from SAP source systems	-	X

Number of Delivered Migration Objects

For the SAP S/4HANA migration cockpit, the predefined data migration objects include:

API call definition, with simulation handling
sender structure definition, with

the source structure/extraction model,
source fields, key definition,
view definition for structure and field visibility

the structure mapping to the data migration API
the field mapping
predefined value mapping and event rules
integration into Data Migration Status app
key mapping to jump to validation app for the migrated instances
calculated view and calculated availability to show objects, structures, and fields based on activated countries and licenses

	SAP S/4HANA 2023 FPS2	SAP S/4HANA Cloud Public Edition 2408
Staging Tables Approach	228	277
Direct Transfer Approach	259	21

You can find details on all available migration objects for the migration cockpit on the SAP Help Portal via these short cuts. Just select your release or use "latest":

SAP S/4HANA Cloud Public Edition: https://help.sap.com/S4_CE_MO
SAP S/4HANA (on premise versions): https://help.sap.com/S4_OP_MO

For the LSMW, a list of ~66 usable SAP migration programs (table SXDA0) with predefined target structures were delivered. Though the list of BAPIs and IDocs seems long, not all of them can be used within LSMW. All data migration objects must be created on your own including source structure, source fields, structure relations, field mapping and conversion rules, translations, file definition and file to target structure mapping.

Supported Migration Methods

The LSMW supports the following migration methods:

Predefined SAP Standard Migration reports
Backend transaction recording and then use this as batch input data migration method
BAPI with BAPI/ALE interface and related IDoc structure and IDoc type.
- BAPIs without IDoc structure can only be used once the IDoc structure and type will be generated via transaction BDBG
IDoc

The SAP S/4HANA migration cockpit supports the following migration methods:

Function module calls (including BAPI) with specific compatibility restrictions (see SAP Note 2590165 and SAP S/4HANA Migration Cockpit - Creating Your Own Function Modules in LTMOM)
CDS (Core Data Services) Behavior Definition (RAP/BO) with specific compatibility restrictions for example a CREATE operation on the root node

	Legacy System Migration Workbench	SAP S/4HANA Migration Cockpit + SAP S/4HANA Migration Object Modeler
BAPI	supported if BAPI has BAPI/ALE interface and related IDoc structure and IDoc type	supported with some restrictions on test run flags and Commit/Rollback handling (restrictions see SAP Note 2590165)
Function modules	not supported	supported (restrictions see SAP Note 2590165)
CDS behavior definition (RAP/BO)	not supported	supported with some restrictions
IDoc	supported	not supported
Own transaction recordings	supported	not supported
Special SAP Migration Programs	supported if migration object, program and target structure is predefined within the SXDA tables (see SAP Note 646002)	not supported

Why Does the Migration Cockpit Not Support the Change of Existing Business Objects?

First of all, the data is not stored directly in the business application tables, neither with the LSMW nor the migration cockpit.
The migration cockpit, like the LSMW, calls an API with a defined target structure to migrate the data into the SAP S/4HANA system.
The APIs used by the migration objects (normally) only support the CREATE method.
It is therefore not the migration cockpit that limits the capability to make a change, it is the API, used within the data migration object, that doesn't support the UPDATE.

In LSMW, it depends on the selected migration method of the business object: If the method doesn't support the update mode, you cannot update the data of the business object as well.

With the migration object modeler, same as in LSMW, the user can create a user-defined data migration object using either a supported API, delivered by SAP or created by themselves to UPDATE data.

Second, the migration cockpit stores the success of a data migration run for a specific migration instance within a data migration project related database table (restart table). Therefore, a successfully migrated migration object instance cannot be migrated again with the same migration project.

Even if the API supported the UPDATE of a business object, you would need to create a new migration project to migrate the same instance.

Third, for specific scenarios, for example, phased-rollout, special EXTEND migration objects are delivered, for example Customer - extend existing record by multiple addresses. With such an EXTEND migration object, you can migrate data for new organization levels (company code, plant, ...) or other structures (addresses, long text). Objects that you can extend with new company code data, are, for example, Customer, Supplier, Product, or G/L account.

To update existing business objects, SAP recommends using existing mass maintenance apps for specific business objects. These mass maintenance apps are built to update or make recurring changes on business objects.

Can I Still Use LSMW to Update Business Objects?

In SAP Note 2287723 it is clearly said that "...the use of LSMW is restricted in the context of data migrations to SAP S/4HANA...". But restricted does not mean forbidden.

The fact that the LSMW is on the Simplification List means that using the tool is not recommended and at the user's own responsibility. Esp. as there is no further support or new functionality released for this tool.

If you want to create a new migration object or update existing data and a transaction or a BAPI/IDoc that supports the create or update method exists and can still be used in SAP S/4HANA, you can still use the LSMW. But as user, you must first check if the data migration method, you want to use, has any restrictions for SAP S/4HANA.

It is also your choice to use the LTMOM to create your own data migration objects using change-APIs.
In both tools, you always need to create such user-defined migration objects on your own.

The effort with LTMOM is often less than with LSMW as you can make use of predefined rules.

Data Migration Demystified: Legacy System Migration Workbench vs. SAP S/4HANA Migration Cockpit

What Is the Difference Between the Legacy Migration Workbench (LSMW) and the SAP S/4HANA Migration Cockpit?

Legacy Migration Workbench (LSMW)

SAP S/4HANA Migration Cockpit

What Are the Main Differences Between LSMW and the Migration Cockpit?

Tool Definition

Supported Data Sources

Number of Delivered Migration Objects

Supported Migration Methods

Why Does the Migration Cockpit Not Support the Change of Existing Business Objects?

Can I Still Use LSMW to Update Business Objects?

See Also