Configuration Reasoning and Ontology For Web

Configuration plays a central role in the deployment and management of Web infrastructures and applications. A configuration often consists of assigning "values" to a pre-defined set of parameters defined in one or more files. Although the task of assigning values to (configuration) parameters looks simple, configuring infrastructures and applications is a very complex process. In this paper we present a framework for defining and analyzing configuration of an Apache server. We define the notion of "configuration space" of an Apache server as a set of possible values that can be assigned to configuration parameters. We then define the notion of an "obstacle" and "forbidden region" in the configuration space that should be avoided. We model configuration space using a logical framework based on OWL (Web ontology language). The obstacles and forbidden regions in the configuration space are modeled as constraints in the logical framework. These obstacles and forbidden regions are essentially "anti-patterns" that a typical installation should avoid. Given an instance of a configuration (that is, a "point" in the configuration space) we then check if the instance is "obstacle free" using logical reasoning.