The Cassandra Reaper tool is used to schedule automatic repairs for the data in Cassandra. The repairs are scheduled in the background. Reaper is a centralized, stateful, and highly configurable tool for running Apache Cassandra repairs against single or multi-site clusters.
The Reaper is installed automatically when Cassandra is installed. The directory for the reaper is <installation directory>/apache-cassandra/reaper. Reaper is started automatically when Cassandra is started. Reaper is pre-configured with a repair schedule.
You can view the repair status for Reaper on the UI. For more information, see Checking repair status. If repairs do not occur, you must restart Reaper for the automatic data repairs to start. For more information, see Starting and stopping the Reaper manually.