An SAP System comprises one or several SAP Instances and a Database. It corresponds to SAP products like SAP R/3, SAP R/3 Enterprise, SAP NetWeaver, SAP S/4 HANA, etc.
In terms of SAP, the instances of an SAP System share the same
SID (SAP system ID).
In Avantra terms, an SAP System is uniquely identified by the so-called Unified SAP SID. By convention, the Unified SAP SID consists of the SAP System Identifier (SID) with a prefix or suffix to make the Unified SAP SID unique within Avantra installation. In order to avoid confusion, we use the term Real SAP SID to refer to the SID within Avantra.
If you want to manage or monitor an SAP System, you need to manage or monitor the Physical Server, the Database, the primary application server (in old terminology, the Central instance), and, possibly, additional SAP Instances comprising the whole SAP System.
From a license perspective, you need at least an SAP System license and usually a Physical Server as well. If you have additional SAP Instances, you need additional SAP Instance licenses.
Trex and Web Dispatcher SAP Systems only consist of an SAP Instance without a Database, and hence only need an SAP Instance license.
The Avantra Agent monitors the following SAP Basis Releases:
Releases 4.6C, 4.6D
Releases 7.0x, 7.1x, 7.2x, 7.3x, 7.4x, 7.5x, 7.7.x
Unicode Kernels are supported as well.