Thanks for crisp and to the point article. I have a question, how does the follower redirect the client request to the leader? More precisely, how does ht e follower know who is the current leader?

I have a question, during Leader Election, when a candidate send RequestVote to other nodes, would other nodes send you a No?

Or is it just I send out 4 RequestVote's and I got back 3 yes, So i'm the leader.

But if i get back 2 yes, there is no election.

A node will only become a leader if it receives a vote from the majority of the nodes in the cluster. In your example, receiving only 2 votes probably means there are 2 different nodes trying to become leader (because they timed out around the same time), so there's no election and they need to wait a new timeout to try the process again.

Typo under first paragraph in Log Replication: "...return and error.."

Fixed, thanks.

Thank you for the great article

Many thanks for your article. A great great one! Thanks!