Types of SAP R/3 system copy

SAP R/3 supports two types of system copy:

Heterogeneous system copy

Homogeneous system copy
1.1.1 Heterogeneous system copy
A heterogeneous system copy is used for making a copy of an SAP R/3 system
and changing the operating system and/or the database server. This type of
system copy is generally referred to as a system migration. We do not describe
heterogeneous system copy because it is outside the scope of this redbook.
1.1.2 Homogeneous system copy
HSC is used for making a copy of an SAP R/3 system where the operating
system and the database server are the same on the target system. HSC is
sometimes referred to as a system clone.
In HSC, the target SAP R/3 database server has the same operating system
(such as OS/390 or zOS ) and the same database system (such as DB2 for
OS/390) as the source SAP R/3 system. The contents of the database are
copied from the source SAP R/3 system to the target SAP R/3 system. The SAP
and DB2 version/release of the source and target systems must also be the
same.
SAP R/3 supports two methods for performing an HSC:

Using SAP R/3 Export/Import tools

Using database-specific tools
The SAP R/3 Export/Import procedure uses a standard SAP-supplied
transaction to export the data from the source database to a flat file, and then to
import the data into the target database. This process is not recommended for
large production SAP environments. Typically, this process is used with small
systems that are being used in pilot projects or some development efforts. The
time to accomplish the export-import process with large production systems
makes this process prohibitive.

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