Consensus (Raft).
A group agreeing on one version of the story, even when some members go quiet.
- No, MY version is right!1
Several machines keep copies of the same data. Left to talk over each other, the copies would drift apart.
- You take the chair.2
So they vote one of themselves in as leader — the chair everyone now follows.
- Proposing: set x = 5.3
Every change goes through the leader, who writes it down in order and proposes it to the rest.
- Three of five agree — committed.4
It’s only locked in once more than half the machines have stored it. A majority makes it official.
- 5
Why majority? Any two majorities share at least one machine, and it refuses to back two conflicting stories.
- Chair’s gone quiet — new vote.6
If the leader goes quiet, the survivors notice and elect a new one. A brief pause, but no data lost.
Semicolony semicolony.dev/eli5/consensus/comic