question about the sync phase in the ZAB

[Ax Jiang <ji...@gmail.com>]

HI there

I am new to ZAB and very interested in the ZAB.
My question is that in the paper "Zookeeper's atomic broadcast protocol:
Theory and Practice", in the pseudo code of phase two: sync, in the line
19. If the follower's epoch is not the prospective leader, which means the
epoch of this follower is pretty old, then the state of this follower will
go to the re-election. In the following reelection, since the epoch of this
follower is older it seems data in this follower will never will sync-ed?

I guess I miss something in the reading and any help is appreciated in
advance.

-regards