Types of System Copy
SAP Homogeneous System Copy
An SAP homogeneous system copy is a way to move or copy an SAP system to a new environment. In a homogeneous system copy, the source and target system uses the same operating system (OS) and database (DB) system. The hardware architecture remains the same, or is a certified successor, where SAP supports homogeneous copies as well.
SAP Heterogeneous System Copy
In a heterogeneous system copy, the source and target systems use a different OS or DB. In many cases, a change of the hardware architecture is also involved. The operating anddatabase systems for a heterogeneous system copy are SAP-released combinations of OSand DB versions.
Depending on the method used for executing the heterogeneous system copy, it may be necessary to upgrade the DB or the OS of the source system first. Older SAP system releasesmay require an update. This can happen if the target platform requires a DB or OS versionthat is not compatible with the SAP system version that is to be migrated. New hardware onthe target system may be supported by the latest OS and DB version only.
The decisive factors for performance in an SAP system are the parameter settings in the database, the OS, and the SAP system itself (which depends on the OS and the DB system).
During an OS/DB migration, the old settings cannot simply be taken unchanged. Determining the new parameter values requires an iterative process.
A common reason for performing a heterogeneous system copy is the change of a DB or OS for one of the following reasons:
- Hardware enhancements
- Performance improvements
- Availability of new technologies
- Administrative efficiency
- Cost reduction
- Guarantee against hardware or software becoming obsolete
- Standardization through group-wide platform strategy
The following table provides an overview of system copy types that are homogeneous even though they appear to be heterogeneous. The table is valid when using R3LOAD or JLOAD. Homogeneous system copies using Backup/Restore require the same database version on source and target systems, or must be upgraded after the system copy.
If the hardware architecture in a system copy changes, but the OS and the DB type stays the same, it is a homogeneous system copy. In other words, if the OS is called the same on the source and target, it is a homogeneous system copy if the DB does not change. This does not automatically imply the possibility of a backup/restore to copy the DB (for example, system copy from Solaris SPARC to Solaris Intel). In this case it is treated as a homogeneous system copy and an SAP OS/DB migration check is not required. SAP assumes that the OS behaviour will be the same regardless of the underlying hardware architecture