Stabilty improvements for split votes.

Was incorrectly resetting term and exiting on failed vote. Also was not properly stepping down when we were a candidate and saw an entry from a leader.

Signed-off-by: Derek Collison <derek@nats.io>

server/raft.go

@@ -1361,13 +1361,6 @@ func (n *raft) runAsCandidate() {
 					n.switchToLeader()
 					return
 				}
-			} else {
-				n.Lock()
-				n.term = vresp.term
-				n.writeTermVote()
-				n.Unlock()
-				n.switchToFollower(noLeader)
-				return
 			}
 		case vreq := <-n.reqs:
 			n.processVoteRequest(vreq)
@@ -1440,6 +1433,15 @@ func (n *raft) processAppendEntry(ae *appendEntry, sub *subscription) {
 		return
 	}
 
+	// If we received an append entry as a candidate we should convert to a follower.
+	if n.state == Candidate {
+		n.debug("Received append entry in candidate state from %q, converting to follower", ae.leader)
+		n.term = ae.term
+		n.Unlock()
+		n.stepdown <- ae.leader
+		return
+	}
+
 	// Catching up state.
 	catchingUp := n.catchup != nil
 	// Is this a new entry or a replay on startup?