Dear All,
Please check this for the description of Logical Systems,
Logical Systems :
A logical system is an application system in which the applications are coordinated to work in one common database. In SAP terms, a logical system corresponds to a client.
The distribution of data between systems makes it necessary to identify each system as a unique logical system.'Logical System' is used to identify an individual client in a system, for ALE communication between SAP systems. That's why you see a field for 'logical system' in the client master data in SCC4 (table T000). You use logical systems in ALE config - this should be documented further in the IMG guide, or SALE and
BALE transactions.
The logical system is important in the following SAP areas:
. Communication between two or more logical systems
ALE business process (e.g. Cost Center Accounting): Defines the system in which a particular application is running. Only in this system can master data can be changed.
Business Object Repository: The name of the logical system in which an object is located is always contained in the key of that Workflow object.
In the following steps, you must define each client as a logical system by first of all defining logical systems and then assigning the clients to the corresponding logical systems.
Note :
Assignments must be unique (that is, one client can only be assigned to one logical system.
a.)More than one client must never be assigned to the same logical system.
b.)The logical system must be unique across the company. It must not be used by any other system in the ALE network.The same applies to pre-production systems and production systems: the pre-production system must be assigned to a different logical system from the production system.
c.)If the logical system of a document reference is not initial and is different from your own system, the system assumes that the document is located on another system.
Recommendation
Sending and Receiving Systems :
The sending and receiving systems must be configured for messaging. You have to define:
a.)The logical systems for all participating systems
b.)Communication parameters for a logical destination in the network.
Define Logical System :
In this step, you can define the logical systems in your distributed system.
Caution :
Logical systems are defined cross-client.
Activities :
1. To create a logical system, choose Edit -> New Entries.
2. Enter a name for the logical system that you want to create.
3. Enter a description of the logical system.If you want to change this entry:
a) Select the appropriate line.
b) Choose Edit -> Change field contents.
c) Enter the new text.
d) Choose Replace.
4. Save your entries.
Systems in Network
Communication between the systems is based on the RFC interface.
You have to define settings for the RFC destination.
The RFC interface enables data to be exchanged between systems by synchronous or asynchronous processing.
ALE generally uses asynchronous processing.