From bf78ed8a94a0b81e266a4a56a7f5367952cbd31a Mon Sep 17 00:00:00 2001
From: zbynek001 <zbynek001@gmail.com>
Date: Thu, 19 Jul 2018 19:57:36 +0200
Subject: [PATCH] confirm TakeOverFromMe when singleton already in oldest state

---
 .../Akka.Cluster.Tools/Singleton/ClusterSingletonManager.cs | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/contrib/cluster/Akka.Cluster.Tools/Singleton/ClusterSingletonManager.cs b/src/contrib/cluster/Akka.Cluster.Tools/Singleton/ClusterSingletonManager.cs
index e79459db1c5..c519b70a88a 100644
--- a/src/contrib/cluster/Akka.Cluster.Tools/Singleton/ClusterSingletonManager.cs
+++ b/src/contrib/cluster/Akka.Cluster.Tools/Singleton/ClusterSingletonManager.cs
@@ -903,6 +903,12 @@ private void InitializeFSM()
                 {
                     return GoToHandingOver(oldest.Singleton, oldest.SingletonTerminated, Sender);
                 }
+                else if (e.FsmEvent is TakeOverFromMe)
+                {
+                    // already oldest, so confirm and continue like that
+                    Sender.Tell(HandOverToMe.Instance);
+                    return Stay();
+                }
                 else if (e.FsmEvent is Terminated terminated && e.StateData is OldestData o && terminated.ActorRef.Equals(o.Singleton))
                 {
                     return Stay().Using(new OldestData(o.Singleton, true));