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+====== Multiple Component Instances via Configuration ======
+In OSGi it is really simple and straightforward to create a service. Services in OSGi are singletons by default.
+But sometimes you need multiple instances of the same service just with different configurations. And luckily OSGi also supports this.
+===== Implementation =====
+Just write your DS component as always as you would for a single instance component. Now add
+  configuration-policy="require"
+to the component xml (or add it via annotations. I am a bit old school and still write the xml =). That means that a component will only be activated if there is a configuration for it.
+You don't need to implement //ManagedService// for getting the configuration. So you can skip this step in your coding habit ;-).
+===== Configuration =====
+Here comes the tricky part. The normal configuration (always using //file install// for picking up the configuration) has the filename like the //service.pid// attribute with the suffix //cfg//. But that would mean that we would create a normal configuration ... and we wouldn't get multiple instances.
+You syntax for the configuration file for multiple instances of a component (when using //file install//)is
+  <component.name>-<new_service_pid>.cfg
+The configuration file itself doesn't need the //service.pid// entry.
+===== Configuration Modification =====
+And if a configuration changes the component will be deactivated, deregistered and removed and a new component instance will be created with the updated configuration.
+{{tag>osgi}}

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