Configuration is always a single file; either Configuration.xml when running in the studio's embedded server, or a context file (*.xml) when deploying using the standalone server.
These files are similar, but not identical, and while a context file is required to deploy the most basic application in the standalone server, the Configuration.xml file is not required unless you wish to override some default (such as a replacement or additional data source).
The configuration files contain definitions to one or more data sources (= one or more databases), each providing access to the multiple tables, views, stored procedures, and other objects the database contains, dependent on the privileges defined for the user name specified.
Data sources are defined using the <Resource> element, defined and used in tomcat configurations (in the studio's Configuration.xml you can also use the alternate <Data Source> element) - See here for details on the different attributes which should be used in the definition.
Additional details can be found in the Tersus Server - Cross Platform installation instructions, found here (scroll down to the 2.2. Create an Application Context File section).
You can use the Configurator application as an aid in creating either files (currently supporting a single data source definition, for the default jdbc/Main resource).
You're welcome to post additional questions (or a problematic configuration file) to the forum, and we'll be happy to review/assist.
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