The event streaming plugin is open source and available to all Hyperledger Besu users.
When using the event streaming plugin, Hyperledger Besu stores the block number and hash for the latest event published in the message broker in a local database. Storing the event metadata enables Hyperledger Besu to avoid duplicating an already published event in a node crash or similar event.
By default, event metadata is stored. Storing the metadata has a small impact on performance. To disable, use the
--plugin-kafka-metadata-db-enabled command line option.