Turn on gossip logging for flaky test + improve test error msg (#23868)

akka-cluster-sharding/src/multi-jvm/scala/akka/cluster/sharding/MultiDcClusterShardingSpec.scala

@@ -10,7 +10,6 @@ import akka.actor.ActorRef
 import akka.actor.Address
 import akka.actor.Props
 import akka.cluster.Cluster
-import akka.cluster.ClusterEvent._
 import akka.cluster.MemberStatus
 import akka.cluster.sharding.ShardRegion.CurrentRegions
 import akka.cluster.sharding.ShardRegion.GetCurrentRegions
@@ -55,11 +54,12 @@ object MultiDcClusterShardingSpecConfig extends MultiNodeConfig {
   val fourth = role("fourth")
 
   commonConfig(ConfigFactory.parseString(s"""
-    # DEBUG because of failing test, issue #23582
+    # DEBUG because of failing test, issue #23741
     akka.loglevel = DEBUG
     akka.cluster.debug.verbose-heartbeat-logging = on
+    akka.cluster.debug.verbose-gossip-logging = on
     akka.actor.provider = "cluster"
-    akka.remote.log-remote-lifecycle-events = off
+    akka.remote.log-remote-lifecycle-events = on
     akka.cluster.auto-down-unreachable-after = 0s
     """))
 
@@ -90,10 +90,12 @@ abstract class MultiDcClusterShardingSpec extends MultiNodeSpec(MultiDcClusterSh
     runOn(from) {
       cluster join node(to).address
       startSharding()
-      within(15.seconds) {
-        awaitAssert(cluster.state.members.exists { m ⇒
-          m.uniqueAddress == cluster.selfUniqueAddress && m.status == MemberStatus.Up
-        } should be(true))
+      withClue(s"Failed waiting for ${cluster.selfUniqueAddress} to be up. Current state: ${cluster.state}" + cluster.state) {
+        within(15.seconds) {
+          awaitAssert(cluster.state.members.exists { m ⇒
+            m.uniqueAddress == cluster.selfUniqueAddress && m.status == MemberStatus.Up
+          } should be(true))
+        }
       }
     }
     enterBarrier(from.name + "-joined")
@@ -102,7 +104,7 @@ abstract class MultiDcClusterShardingSpec extends MultiNodeSpec(MultiDcClusterSh
   def startSharding(): Unit = {
     ClusterSharding(system).start(
       typeName = "Entity",
-      entityProps = Props[Entity],
+      entityProps = Props[Entity](),
       settings = ClusterShardingSettings(system),
       extractEntityId = extractEntityId,
       extractShardId = extractShardId)

akka-remote/src/main/resources/reference.conf

@@ -347,8 +347,6 @@ akka {
     # writer exceeds this limit. It can be disabled by setting the value to off.
     log-buffer-size-exceeding = 50000
 
-
-
     # After failed to establish an outbound connection, the remoting will mark the
     # address as failed. This configuration option controls how much time should
     # be elapsed before reattempting a new connection. While the address is