Camunda 8 | State storage & Event storage

[StephanHaarmann]

Hi @saiprasad.krishnamur,

1. The Zeebe-Brokers implement the RAFT algorithm. The leader distributes events to its followers using this protocol without an external broker.
2. The workers retrieve work from the engine using the gRPC api.
3. The engine state is persisted. Therefore, a high-performance key value store (RocksDB) is used, which cannot be accessed outside the engine. Reads @korthout response in the following thread to learn more about scalability and fault tolerance:

Does Zeebe store its state in RocksDB or any database?

Hi @sherry-ummen, Zeebe does not use a centralized, external or shared database. @deepthi gave a great talk about scaling workflow engines which discusses the problem of such databases in the first 2 minutes and then goes on to explain how Zeebe solves the problems of scaling and fault tolerance Scaling a distributed workflow engine (CamundaCon 2019) - YouTube. You can also read more about our technical concepts here. Lastly, to more directly answer your question about RocksDB. Zeebe does us…