Multiple ECC clients configured to APO

Question

Folks,
If multiple ECC clients (001, 002, 003) are configured with a single APO client(001), how does APO system deal with this without causing data issues.
Say if I updated Material master in all these 3 ECC clients, which version will be refelected in APO system.
TIA

Answer 1

Hi Pat,
Need to maintain different BSG: Business System Group for each R/3  by tcode : /SAPAPO/C2.
"Maintain Business System Group
    Use
    In this IMG activity, you determine the assignment to a business system
    group of the APO System and the SAP R/3 System to be connected. By doing
    this, you create areas with the same naming conventions. These guarantee
    that the same names are used for master data, and also their
    synchronization in distributed system landscapes.
    Requirements
    As an independent logical system, the APO System must, in addition to
    the SAP R/3 Systems, be assigned to a business system group (BSG).
    Activities
    o   Choose New entries.
    o   On the New entries: Overview screen, specify the following
    o   information for the business system group:
        -   An alphanumerical key (maximum of 10 characters).
        -   A description.
    o   Save your entries.
Example 1
An APO System is to be linked with two SAP R/3 Systems (A and B), in
which two different materials (for example a hammer and a screw), have
the same material number (100). Both materials are to be represented as
two different products in the APO System.
Assign both SAP R/3 Systems to different BSGs. Assign the APO System to
one of the BSGs.
o   SAP R/3 System A (Material number 100 = Hammer) -> BSG A
o   SAP R/3 System A (Material number 100 = Screw) -> BSG B
o   APO System -> BSG A
In order to avoid having two identical names and to be able to uniquely
assign the material numbers, you need SAP extension APOCF005. This is an
inbound processing product (transaction SMOD or CMOD).
Material number 100 from BSG A receives, for example, product number 100
in the APO System and material number 100 from BSG B gets product number
100_B. This allows you to uniquely assign the materials.
For inbound processing in the APO System, the following SAP enhancements
are available as customer exits for master data:
o   APOCF001 : Inbound processing location
o   APOCF005 : Inbound processing product
Example 2
An APO System is to be linked with two SAP R/3 Systems (A and B). In SAP
R/3 System A, a particular screw has material number 110. In SAP R/3
System B, it has material number 120. Both material numbers are
represented in the APO System by one product, with product number 110.
Assign both SAP R/3 Systems to different BSGs. If possible, assign the
APO System to the BSG whose data does not have to be renamed.
o   SAP R/3 System A (material number 110 = screw) -> BSG A
o   SAP R/3 System B (material number 120 = screw) -> BSG B
o   APO System (product number 110 = screw) -> BSG A
You use SAP enhancement APOCF005 to convert the local SAP R/3 material
number 120, to the APO product number, 110.
Note
For the time being, this second scenario is only supported for material
masters and product masters. If, for example, the same customer is used
with different BSGs in R/3 Systems A & B, you must create two separate
customer locations in the APO System. This applies for the vendor,
plant, and other master data.