In an Decentralized EWM implementation there are few methods migrating inventory from ECC SAP WM depending on your landscape and EWM design, specifically how many SLOC's that you have, will you be using existing SLoc's or not, and will you be  creating SLoc's etc.

Based on your new design below are the options available.

In my recent implementation; we decided to not use existing SLoc's and use new ones, because of this the first option is the best option for us at the moment (Clear the storage location posting to the cost account).

1 Stock Migration

1.1 Adapt Storage Locations

There are several ways of changing the LE-WM storage location to an EWM storage location, as follows:

• Clear the storage location posting to the cost account
• Consolidate the existing storage location(s) into a new storage location for EWM
• Keep the existing storage location with a temporary switch to an intermediate storage location

Consider the usage of existing or new storage locations for your EWM warehouse. In EWM you can use one or more storage locations in the plant. Two storage locations in one warehouse allow you more flexibility in the availability of the stock. For example, stock in storage location Received On Dock (ROD) has been received in the warehouse but has not been put away into the final bin yet and as such is not available yet for customer orders; stock in storage location Available For Sale (AFS) is stored in the final bin in the warehouse and is ready to be picked for customer orders.

As a general prerequisite you have to download the stock data from LE-WM using the stock migration tool.

Clear the storage location posting to the cost account

1. Maintain the Customizing activity Logistics Execution -> Warehouse Management -> Activities -> Physical Inventory -> Clear Differences (Interface to Inventory Management) as follows:

• Under MM-IM Movement Types for Clearing Inventory, maintain the required movement types. Use movement type 562 for clearing, to facilitate using the transaction for stock data transfer in EWM later. The stock transfer posting in EWM will communicate movement type 561 to LE-WM.
• Under Forbid Clearing of Differences in Inventory Management, deselect the checkbox No diff. posting for the affected storage types.

2. Use the transaction Logistics -> Logistics Execution -> Internal Whse Processes -> Physical Inventory -> In Warehouse Management -> Clear Differences -> Inventory Management on the SAP Easy Access screen to clear the storage types of the storage location and post them to a cost account.

3. Use the transaction Extended Warehouse Management -> Interfaces -> Stock Data Transfer to upload the stock to EWM. With this posting, the LE-WM stock is posted back to the balance sheet account from the cost account. Ensure that the checkbox Do Not Post Data in ERP is deselected during the stock upload.

Note that in this case the financial department probably as to approve the postings.

Consolidate the existing storage location(s) into a new storage location for EWM

1. Use the Stock Migration transaction to upload the stock of a given storage type into a file. You can find it on the SAP Easy Access screen under Extended Warehouse Management -> Migration from LE-WM -> Stock Migration or by using transaction code /SCWM/MIG_STOCK.

2. Create a new storage location, AFS, which is managed by IM.

3. Define an intermediate storage type in LE-WM (X04). Set the putaway strategy to Q = Dynamic coordinate quant number. Ensure that SU management is not active. Be aware that after moving the stock, the information related to handling units and storage unit will get lost. The stock placement and stock removal don‟t need confirmation.

4. Set the storage type to the destination data of the movement type. Select the checkboxes TO Item can be confirmed immediately and Propose Confirmation.

5. Specify the destination storage location and the required movement type in Customizing for Logistics Execution under Warehouse Management -> Interfaces -> Inventory Management -> Define Storage Location Control -> Storage Location Control In Warehouse Management. You can ignore the error message Assignment plant / storage location && to warehouse number & does not exist (LT225). 

6. On the SAP Easy Access screen, choose Logistics -> Logistics Execution -> Internal Whse Processes -> Stock Transfer -> Create Transfer Order -> From Stock List to transfer the stock to the newly created stock type X04.

7. The stock has been transferred to the storage location AFS, however, EWM does not yet recognize it. Thus, you have to upload the stock. On the SAP Easy Access screen, choose Extended Warehouse Management -> Interfaces -> Data Upload -> Stock Data Transfer. During the upload, ensure that the checkbox Do Not Post Data in ERP is selected. The new storage location settings are adapted to reflect the connection to the EWM system.

Keep the existing storage location with a temporary switch to an intermediate storage location

1. Create an intermediate storage location IM00.

2. Carry out the same steps 1, 3, 4, and 5 as in the second variant above.

3. Specify the destination storage location and the required movement type in Customizing for Logistics Execution under Warehouse Management -> Interfaces -> Inventory Management -> Define Storage Location Control -> Storage Location Control In Warehouse Management. You can ignore the error message Assignment plant / storage location && to warehouse number & does not exist (LT225).

4.

a. Create an intermediate storage location (IM00) which is IM-managed. Use transaction code LQ01in LE-WM to post the stock from the existing storage type to the new one. Use movement type 411.

b. Adapt the existing storage location, which is now empty, to reflect the connection to the EWM system. To post the stock in EWM and to post it to the correct storage location in LE-WM, use the Stock Data Transfer transaction. You can find it on the SAP Easy Access screen under Extended Warehouse Management -> Interfaces -> Stock Data Transfer or by using transaction code /SCWM/ISU. Use the BAdI /SCWM/EX_ERP_GOODSMVT_EXT to change the movement type from 561 to 411 and to specify the source storage location. You must make both changes in CT_GOODSMVT_ITEM.

You should execute the stock comparison using transaction code /SCWM/ERP_STOCKCHECK to ensure that LE-WM and EWM have the same stock data on the storage location level.

Map LE-WM Storage Location to EWM

• In LE-WM, the storage locations can be HU-managed or SU-managed. This concept does not apply in EWM. Hence, you should use one of the following options to map the storage location during stock migration. Process the migration by considering the storage location; that is, without migrating stock that is located in more than one storage location. Whenever you want to carry out a migration, change the Customizing to reflect the mapping between the storage location in LE-WM and the storage location in EWM.

For example, assume that there are two storage locations in LE-WM:

o 0088 with storage units

o 0100 that is HU-managed

Assume that you start by migrating the stock which is available in 0088. In this case, you should make an entry for mapping the 0088 storage location in Customizing for Extended Warehouse Management under Interfaces -> ERP Integration -> Goods Movements -> Map Storage Locations from ERP System to EWM.

Once the migration has finished for this storage location, you can delete this mapping and create a new entry for the storage location 0100. So at the end, the stock has been migrated and has the same availability group in EWM.

• Use the existing storage locations, such as 0088 or 0100, for the integration with EWM. Enter the mapping of both storage locations in Customizing and process the migration without considering the storage location in EWM. Once the stock has been uploaded in EWM, you can perform an internal goods movement in order to have the same availability group for all the stock. For more information, see “Integration of SAP ERP with SAP EWM” in the Business Process Repository of SAP Solution Manager.

1. In transaction SOLAR02, select the structure node Configuration.

2. On the Structure tab page, select the Change Configuration Structure button.

3. On the Structure tab page, select the value help for the Configuration Element field.

4. In the displayed structure, choose Solutions/Applications -> SAP EWM -> Basic Settings for SAP EWM (Version number.