Meetup #54 - In Search of an Understandable Consensus Algorithm

Raft is a consensus algorithm for managing a replicated log. It produces a result equivalent to Paxos, and it is as efficient as Paxos, but its structure is different from Paxos; this makes Raft more understandable than Paxos and also provides a better foundation for building practical systems. In order to enhance understandability, Raft separates the key elements of consensus, such as leader election and log replication, and it enforces a stronger degree of coherency to reduce the number of states that must be considered. Raft also includes a new mechanism for changing the cluster membership, which uses overlapping majorities to guarantee safety. Results from a user study demonstrate that Raft is easier for students to learn than Paxos.

Links:

• In Search of an Understandable Consensus Algorithm (paper) (https://ramcloud.stanford.edu/wiki/download/attachments/11370504/raft.pdf)

• Raft: A Consensus Algorithm for Replicated Logs (video) (http://www.youtube.com/watch?v=YbZ3zDzDnrw)