From 7af86685e3909684eb792c4517be67076045a4da Mon Sep 17 00:00:00 2001
From: Jan <jsteemann@users.noreply.github.com>
Date: Fri, 8 Dec 2017 17:33:37 +0100
Subject: [PATCH] when upgrading from 3.1 LastHeartBeatAcked could also have
 been missing, when the 3.1 cluster had not run for long enough (#3974)

---
 arangod/Agency/Supervision.cpp | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/arangod/Agency/Supervision.cpp b/arangod/Agency/Supervision.cpp
index 6e2227fc8b..f0b48e0fae 100644
--- a/arangod/Agency/Supervision.cpp
+++ b/arangod/Agency/Supervision.cpp
@@ -81,16 +81,20 @@ struct HealthRecord {
         version = 2;
         syncStatus = node("SyncStatus").getString();
         if (node.has("SyncTime")) {
-          lastAcked = node("LastAcked").getString();
           syncTime = node("SyncTime").getString();
         }
+        if (node.has("LastAcked")) {
+          lastAcked = node("LastAcked").getString();
+        }
       } else if (node.has("LastHeartbeatStatus")) {
         version = 1;
         syncStatus = node("LastHeartbeatStatus").getString();
         if (node.has("LastHeartbeatSent")) {
-          lastAcked = node("LastHeartbeatAcked").getString();
           syncTime = node("LastHeartbeatSent").getString();
         }
+        if (node.has("LastHeartbeatAcked")) {
+          lastAcked = node("LastHeartbeatAcked").getString();
+        }
       }
       if (node.has("Host")) {
         hostId = node("Host").getString();