Dual Landscape Synchronization (Retrofit) 
In system landscapes in which multiple releases are used, changes can be made in different development systems: This allows new developments to be made in the development system, and errors to be corrected or improvements to be made in a maintenance system for the production system landscape at the same time. The system release levels must be adjusted regularly. Since changes are made in parallel, changes cannot be transported between systems in requests, because current software may be overwritten and inconsistencies can occur. To avoid this, you can perform a controlled import into the target system. This is called retrofitting.
A Phased System Landscape as an Example of System Relationships
Prerequisites
You have applied SAP Note 1468044 in the managed systems.
You have made the relevant settings in Customizing under
SAP Solution Manager 
Capabilities Change Request Management Retrofit 
.The retrofit function is activated in SAP Solution Manager.
For more information about using an RFC trusted/trusting relationship between two SAP systems, see System Users and RFC Destinations with Trusted Systems.
Both systems that are to be part of the retrofit scenario are in the same transport management system (TMS) domain or in linked TMS domains.
You have activated the cross-system object lock in Customizing under
SAP Solution Manager Capabilities Change Request Management Cross-System Object Lock and Downgrade Protection Configure and Activate Cross-System Object Lock .You have set up the following RFC connections
SM_<SID>CLNT<...>_READ
SM_<SID>CLNT<...>_TMW
SM_<SID>CLNT<...>_TRUSTED
for both client 000 and the production client:
from SAP Solution Manager to the development landscape
from SAP Solution Manager to the maintenance landscape
NoteAdditional RFC connections are created automatically when the retrofit scenario is activated in SAP Solution Manager.
For more information, see SAP Note 1175098.
End of the note.Your user has authorization for the following authorization objects in both development systems – both in client 000 and the production client:
S_RFC_ADM
S_TRANSPORT
S_SYS_RWBO
A logical component in the SAP Solution Manager project contains at least one (retrofit) system with the role Retrofit System.
To specify into which system changes are to be imported, you have executed the task Assignments of Postprocessing Systems to Development Systems in the overview of the task list.
When you define retrofit systems, the system only offers you transport requests from the development systems you assigned to the retrofit systems when you started a preprocessing task.
If you make no assignments, the system offers you all transport requests from all development systems when you start the retrofit. You can make this assignment as often as required. The assignment is updated each time.
NoteTo process new and ABAP Dictionary objects, the target system for the retrofit must have Basis Release 6.20 or higher.
End of the note.You have created transport requests for the retrofit in the retrofit system into which you want to import the changes from the maintenance system.
Features
The following retrofit processes are available:
Process | Object Types Supported | Can Be Used For |
Automatic import | All object types with the exception of BW objects and non-ABAP objects |
|
Using the Correction Workbench and Business Configuration Sets as postprocessing tools |
|
|
Manual retrofit | Objects that cannot be imported automatically and that are not supported by the postprocessing tools | All other objects |
You can use the following functions to prepare the retrofit:
Retrofit status display for transport requests and objects
Green: Can be imported using the automatic import
Yellow: Can be imported using the postprocessing tools
Red: Objects have to be transferred manually to the retrofit system
Sequence dependency
The sequence dependency indicates whether a transport request is dependent on another transport request. For example, transport request A contains object X, which already exists in transport request B. This means there is a sequence dependency between transport requests A and B.
A transport request can have a sequence dependency to more than one other transport request (different objects are in different transport requests).
There is just one sequence dependency for an object X between transport request A and transport request B if transport request B is the only request with object X or is the request that was last released.
There can also be a sequence dependency between transport request B and a third transport request.
The sequence dependency is based on the objects in the object list for the entire retrofit queue. The sequence dependency is updated or deleted as soon as the retrofit for a transport request is completed.
If there is no sequence dependency, and some requests have not yet been processed, the system displays a message. You can specify in the Customizing settings whether the message is to be displayed as a warning or as an error.
Consistency check
The system checks whether the retrofit was prepared correctly:
Have transport requests been created in the retrofit system into which you want to import the changes from the maintenance system?
Has the execution sequence of the transport requests to be imported been observed?
Does the transport request contain objects from Notes that could cause conflicts during the import?
Display for various logs with messages for the transport requests
Display and processing of BC Sets for transport requests that contain Customizing objects
Call to the TMS Alert Viewer
For more information, see Displaying the TMS Alert Viewer.
Activities
You start the retrofit directly from your change document.
You check the status of each of the transport requests and the objects in the requests.
You perform the retrofit for your transport requests.