== Guarantees ==
What kind of guarantees does ZooKeeper provide?
Sequential consistency: Updates from any particular client are applied in the order Atomicity: Updates either succeed or fail. Single system image: A client will see the same view of the system, The new server will not accept the connection until it has caught up. Durability: Once an update has succeeded, it will persist and will not be undone. Timeliness: Rather than allowing a client to see very stale data, a server would prefer shut down.