From 7948268c09af8bc024a1d29ee2710bd22dec6462 Mon Sep 17 00:00:00 2001
From: David Turner <david.turner@elastic.co>
Date: Mon, 6 Aug 2018 12:35:18 +0100
Subject: [PATCH] Can only deactivate an active PeerFinder

---
 server/src/main/java/org/elasticsearch/discovery/PeerFinder.java | 1 +
 1 file changed, 1 insertion(+)

diff --git a/server/src/main/java/org/elasticsearch/discovery/PeerFinder.java b/server/src/main/java/org/elasticsearch/discovery/PeerFinder.java
index 8c230dd93a6ad..10d4115352da7 100644
--- a/server/src/main/java/org/elasticsearch/discovery/PeerFinder.java
+++ b/server/src/main/java/org/elasticsearch/discovery/PeerFinder.java
@@ -102,6 +102,7 @@ public void activate(final DiscoveryNodes lastAcceptedNodes) {
 
     public void deactivate(DiscoveryNode leader) {
         synchronized (mutex) {
+            assert active;
             logger.trace("deactivating and setting leader to {}", leader);
             active = false;
             handleWakeUp();