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1. l The leader starts accepting connections from followers.
2. f Followers connect the the leader and send SERVERINFO(lastZxid, info).
3. l The leader sends SERVERINFO(lastZxid, info) to followers that connect.
4. l The leader waits for a quorum of followers to connect all of whom has:
   • f.currentEpoch <= l.currentEpoch
   • if f.currentEpoch == l.currentEpoch, then f.lastZxid <= l.lastZxid
   l Once the leader has quorum, it stops accepting connections, and sends NEWEPOCH(e) to all followers, where e is greater than all f.acceptedEpoch in the quorum.
5. f Followers send ACK(e<<32) if e > f.acceptedEpoch. (If e < f.acceptedEpoch, the follower will abandon the leader. If e == f.acceptedEpoch, the follower will not send ACK(e<<32), but will still maintain the connection to the leader.)
6. l The leader waits for all followers to ack NEWEPOCH(e)
7. l If the following conditions are not met for all connected followers, the leader disconnects followers and goes back to leader election:
   • f.currentEpoch <= l.currentEpoch
   • if f.currentEpoch == l.currentEpoch, then f.lastZxid <= l.lastZxid

Note, if a follower is connecting, but the leader is already established (in phase 3) the follower follows the phases, but the leader ignores any ACKs.

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