onfigure and customise the severities that are handled by CMS. Indeed, severities are configurable and customizable. By default, the severity level configuration file "SeverityInfo.conf" defines seven severity levels: Critical, Major, Minor, Warning, Clear, Info and Unknown. The configuration file must contain at least four severity levels, which must include Clear, Info and Unknown. These three severities are used internally by CMS and are mandatory for its functioning. Any number of severity levels, also called severity nodes, can be added to the configuration file and each should have a unique name. The severities defined in the configuration file are logically ordered to form a tree structure, the "severity tree". The "Clear" severity level is the root of the tree. The criticality of each severity defined is measured by its distance from the Clear node of the severity tree. The greater the distance from the Clear node, the more critical is the severity. "Critical" is the highest severity. Severities can be defined either above or below the "Clear" node but not on either side. The Severity API is used to access properties of the severities from user-written code. 11.2.11.6 Front-end (FE) Server Whenever CMS is started, one FE server is started along with the BE server. Apart from this, it is possible also to run standalone FE server(s), when there is a need for more scalability - in particular, when there is a need to connect more clients. The FE server can be started and run in two ways, either in the same JVM as that of the BE or in a different JVM. Predictably, the flow of control between the BE and the FE is different in each case. 11 Configuration Management special session FE runs as process interface Figure 11.17 Starting BE and FE in the same JVM. special session Figure 11.18 Starting BE and FE in different JVMs. Starting the BE and FE servers in the same JVM means starting the CMS, that is the BE-FE combination, and a particular relationship is then set up between the BE and FE servers. When CMS is st