D9Leader election (Raft)

The problem

1 s on screen = 100 ms

When the leader dies, how do the rest agree on one new leader, and only one?

One leader, chosen once

Three copies of a database, one in Europe and two in the Americas. Copy B always leads; the others pass writes to it.

Live metrics for each version of the scene
Fixed leader	Anyone leads	Majority
0%	33%	34%
0	0	0
—	33%	34%
—	1	1

D9Leader election (Raft)

A group of copies needs one boss at a time. When it dies, the rest must agree on a new one without electing two.