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Geronimo provides two OSGi frameworks: Eclipse Equinox and Apache Felix. You can easily configure which OSGi framework is used at runtime by updating the etc/onfig.properties configuration file. By default, Geronimo server uses Equinox as its default OSGi runtime. The following example show how to configure Geronimo to use Felix as its OSGi framework.
The config.properties file is the system properties file of underlying OSGi framework of Geronimo, in which stores the initial configuration parameters to start up the framework.
Save the file and restart the server.