Directory structure
The directory layout of a Karaf installation is as follows:
/bin: startup scripts
/etc: configuration files
/data: working directory
/cache: OSGi framework bundle cache
/generated-bundles: temporary folder used by the deployer
/log: log files
/deploy: hot deploy directory
/instances: directory containing child instances
/lib: contains the bootstrap libraries
/lib/ext: directory for JRE extensions
/lib/endorsed: directory for endorsed libraries
/system: OSGi bundles repository, laid out as a Maven 2 repository
The data folder contains all the working and temporary files for Karaf. If you want to restart from a clean state, you can wipe out this directory, which has the same effect as using the clean option.