Recon is the Web UI and analytics service for Ozone. It’s an optional component, but strongly recommended as it can add additional visibility.

Recon collects all the data from an Ozone cluster and store them in a SQL database for further analyses.

  1. Ozone Manager data is downloaded in the background by an async process. A RocksDB snapshots are created on OM side periodically, and the incremental data is copied to Recon and processed.
  2. Datanodes can send Heartbeats not just to SCM but Recon. Recon can be a read-only listener of the Heartbeats and updates the local database based on the received information.