# Revision history [back]

Hello,

Using ./bin/karaf clean will start the container without any previously installed features, only with the default ones.

To completely clean the MD-SAL data, you should use this command at the root of the karaf directory: rm -rf data/* journal/* snapshots/*

The journal is event source based where each entry contains the affects of a transaction. On startup, the journal entries are played back to rebuild the data tree. Snapshots are taken periodically to avoid the journal getting too large.

A snapshot is just a flat file containing the serialized data tree. When a snapshot is taken, the journal entries are deleted. On startup, akka first plays back the last snapshot and then the journal entries.

Hope this helps, Alexis