Managing a SUSE Linux™ system requires direct low-level access to the system which generally means reading and writing configuration data. Of course this could be done manually by a knowledgeable person using a conventional editor. A more comfortable and in most cases safer way is to use YaST. Consequently YaST must be able to handle this configuration data on the system level. By handling the original data YaST activities take into account manual editing that might also occur. Thus nobody is forced to use YaST exclusively for configuration tasks.

In YaST the access to system configuration data is realized by means of a special component (or layer if you prefer), the System Configuration Repository (SCR) (see below and Access to the System (SCR in General)). The SCR component basically consists of a number of so-called agents that have been created to accomplish a specific kind of access. For example there is an agent to run shell-commands and there is another one that reads and writes ASCII-files of a specific format. Additionally there are agents that provide access to the system hardware e.g. by taking hold on the proc-file-system.

All these agents are gathered together under a common hood, the SCR-API that can be used from within the YaST-modules in a consistent way. In summary the SCR provides kind of a view on all kinds of data, either YaST2 internal data, original system configuration files or hardware data.