I've been using Maven to deploy my bundles over a felix server.
One of the things that fascinates me about Felix/OSGi is if i have configured a component with some values and i deploy my bundle again, even though the @Activate method will be called again for that configuration but my values which i've put there before deployment still persist.
How is Felix able to achieve this and is the configuration shown at /system/console/configMgr not an instance of my Java class used to create the OSGi Component ?
It's the job of the Configuration Admin service (for which Apache Felix provides an implementation) to deal with those details. Ideally, the "how" is irrelevant because those are implementation details, but if you are running an OSGi framework in a specialized environment (an embedded device for example), you would have to select a Configuration Admin provider that works within the limits of the host platform.
Under the hood, the Felix Configuration Admin service uses one or more PersistenceManagers to persist and retrieve the configuration data for your managed services. If you're curious about these implementation details you can read about them on the Felix website or you can take a look at the source code.