The broker died and performed a failover, need to know the cause.

Issue

• we did see that the broker had died on the master server and failed over it had to be restarted to get the master Back.
• we need to know the cause for the broker to die.
• In thread-dump we see

"Thread-25 (ActiveMQ-server-org.apache.activemq.artemis.core.server.impl.ActiveMQServerImpl$5@305b7c14)" Id=121 BLOCKED on org.apache.activemq.artemis.utils.SoftValueHashMap@268d16db owned by "Thread-22 (ActiveMQ-server-org.apache.activemq.artemis.core.server.impl.ActiveMQServerImpl$5@305b7c14)" Id=118
    at org.apache.activemq.artemis.core.paging.cursor.impl.PageCursorProviderImpl.getPageCache(PageCursorProviderImpl.java:136)
    -  blocked on org.apache.activemq.artemis.utils.SoftValueHashMap@268d16db
    at org.apache.activemq.artemis.core.paging.cursor.impl.PageSubscriptionImpl.internalGetNext(PageSubscriptionImpl.java:384)
    at org.apache.activemq.artemis.core.paging.cursor.impl.PageSubscriptionImpl.access$2000(PageSubscriptionImpl.java:62)
    at org.apache.activemq.artemis.core.paging.cursor.impl.PageSubscriptionImpl$CursorIterator.moveNext(PageSubscriptionImpl.java:1247)
    -  locked java.util.LinkedList@28bdadd5
    -  locked org.apache.activemq.artemis.core.paging.cursor.impl.PageSubscriptionImpl@5c1844c7
    at org.apache.activemq.artemis.core.paging.cursor.impl.PageSubscriptionImpl$CursorIterator.next(PageSubscriptionImpl.java:1218)
    at org.apache.activemq.artemis.core.paging.cursor.impl.PageSubscriptionImpl$CursorIterator.hasNext(PageSubscriptionImpl.java:1340)
    -  locked org.apache.activemq.artemis.core.paging.cursor.impl.PageSubscriptionImpl$CursorIterator@126dba51
    at org.apache.activemq.artemis.core.server.impl.QueueImpl.checkDepage(QueueImpl.java:2417)
    at org.apache.activemq.artemis.core.server.impl.QueueImpl.deliverAsync(QueueImpl.java:806)
    at org.apache.activemq.artemis.core.server.impl.ServerConsumerImpl.forceDelivery(ServerConsumerImpl.java:1093)
    at org.apache.activemq.artemis.core.server.impl.ServerConsumerImpl.promptDelivery(ServerConsumerImpl.java:1085)
    at org.apache.activemq.artemis.core.server.impl.ServerConsumerImpl.receiveCredits(ServerConsumerImpl.java:785)
    at org.apache.activemq.artemis.core.server.impl.ServerSessionImpl.receiveConsumerCredits(ServerSessionImpl.java:1377)
    at org.apache.activemq.artemis.core.protocol.core.ServerSessionPacketHandler.onSessionConsumerFlowCredit(ServerSessionPacketHandler.java:733)
    at org.apache.activemq.artemis.core.protocol.core.ServerSessionPacketHandler.onMessagePacket(ServerSessionPacketHandler.java:282)
    at org.apache.activemq.artemis.core.protocol.core.ServerSessionPacketHandler$$Lambda$69/126077847.onMessage(Unknown Source)
    at org.apache.activemq.artemis.utils.actors.Actor.doTask(Actor.java:33)
    at org.apache.activemq.artemis.utils.actors.ProcessorBase.executePendingTasks(ProcessorBase.java:66)
    at org.apache.activemq.artemis.utils.actors.ProcessorBase$$Lambda$4/1107217291.run(Unknown Source)
    at org.apache.activemq.artemis.utils.actors.OrderedExecutor.doTask(OrderedExecutor.java:42)
    at org.apache.activemq.artemis.utils.actors.OrderedExecutor.doTask(OrderedExecutor.java:31)
    at org.apache.activemq.artemis.utils.actors.ProcessorBase.executePendingTasks(ProcessorBase.java:66)
    at org.apache.activemq.artemis.utils.actors.ProcessorBase$$Lambda$4/1107217291.run(Unknown Source)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at org.apache.activemq.artemis.utils.ActiveMQThreadFactory$1.run(ActiveMQThreadFactory.java:118)

    Number of locked synchronizers = 1
    - java.util.concurrent.ThreadPoolExecutor$Worker@4f3771f7



"Thread-22 (ActiveMQ-server-org.apache.activemq.artemis.core.server.impl.ActiveMQServerImpl$5@305b7c14)" Id=118 RUNNABLE
    at io.netty.util.internal.PlatformDependent0.copyMemory(PlatformDependent0.java:571)
    at io.netty.util.internal.PlatformDependent.copyMemory(PlatformDependent.java:576)
    at io.netty.buffer.UnpooledHeapByteBuf.setBytes(UnpooledHeapByteBuf.java:258)
    at io.netty.buffer.AbstractByteBuf.writeBytes(AbstractByteBuf.java:1080)
    at io.netty.buffer.AbstractByteBuf.writeBytes(AbstractByteBuf.java:1072)
    at io.netty.buffer.WrappedByteBuf.writeBytes(WrappedByteBuf.java:778)
    at org.apache.activemq.artemis.core.message.impl.CoreMessage.reloadPersistence(CoreMessage.java:1207)
    at org.apache.activemq.artemis.core.message.impl.CoreMessagePersister.decode(CoreMessagePersister.java:69)
    at org.apache.activemq.artemis.core.message.impl.CoreMessagePersister.decode(CoreMessagePersister.java:26)
    at org.apache.activemq.artemis.spi.core.protocol.MessagePersister.decode(MessagePersister.java:106)
    at org.apache.activemq.artemis.core.paging.impl.PagedMessageImpl.decode(PagedMessageImpl.java:115)
    at org.apache.activemq.artemis.core.paging.impl.Page.read(Page.java:197)
    at org.apache.activemq.artemis.core.paging.impl.Page.readFromMapped(Page.java:177)
    at org.apache.activemq.artemis.core.paging.impl.Page.read(Page.java:128)
    -  locked org.apache.activemq.artemis.core.paging.impl.Page@1e419c6c
    at org.apache.activemq.artemis.core.paging.cursor.impl.PageCursorProviderImpl.readPage(PageCursorProviderImpl.java:170)
    at org.apache.activemq.artemis.core.paging.cursor.impl.PageCursorProviderImpl.getPageCache(PageCursorProviderImpl.java:151)
    -  locked org.apache.activemq.artemis.utils.SoftValueHashMap@268d16db
    at org.apache.activemq.artemis.core.paging.cursor.impl.PageSubscriptionImpl.internalGetNext(PageSubscriptionImpl.java:384)
    at org.apache.activemq.artemis.core.paging.cursor.impl.PageSubscriptionImpl.access$2000(PageSubscriptionImpl.java:62)
    at org.apache.activemq.artemis.core.paging.cursor.impl.PageSubscriptionImpl$CursorIterator.moveNext(PageSubscriptionImpl.java:1247)
    -  locked java.util.LinkedList@377a73df
    -  locked org.apache.activemq.artemis.core.paging.cursor.impl.PageSubscriptionImpl@483b822
    at org.apache.activemq.artemis.core.paging.cursor.impl.PageSubscriptionImpl$CursorIterator.next(PageSubscriptionImpl.java:1218)
    at org.apache.activemq.artemis.core.paging.cursor.impl.PageSubscriptionImpl$CursorIterator.hasNext(PageSubscriptionImpl.java:1340)
    -  locked org.apache.activemq.artemis.core.paging.cursor.impl.PageSubscriptionImpl$CursorIterator@1f8a9585
    at org.apache.activemq.artemis.core.server.impl.QueueImpl.checkDepage(QueueImpl.java:2417)
    at org.apache.activemq.artemis.core.server.impl.QueueImpl.deliverAsync(QueueImpl.java:806)
    at org.apache.activemq.artemis.core.server.impl.ServerConsumerImpl.forceDelivery(ServerConsumerImpl.java:1093)
    at org.apache.activemq.artemis.core.server.impl.ServerConsumerImpl.promptDelivery(ServerConsumerImpl.java:1085)
    at org.apache.activemq.artemis.core.server.impl.ServerConsumerImpl.receiveCredits(ServerConsumerImpl.java:785)
    at org.apache.activemq.artemis.core.server.impl.ServerSessionImpl.receiveConsumerCredits(ServerSessionImpl.java:1377)
    at org.apache.activemq.artemis.core.protocol.core.ServerSessionPacketHandler.onSessionConsumerFlowCredit(ServerSessionPacketHandler.java:733)
    at org.apache.activemq.artemis.core.protocol.core.ServerSessionPacketHandler.onMessagePacket(ServerSessionPacketHandler.java:282)
    at org.apache.activemq.artemis.core.protocol.core.ServerSessionPacketHandler$$Lambda$69/126077847.onMessage(Unknown Source)
    at org.apache.activemq.artemis.utils.actors.Actor.doTask(Actor.java:33)
    at org.apache.activemq.artemis.utils.actors.ProcessorBase.executePendingTasks(ProcessorBase.java:66)
    at org.apache.activemq.artemis.utils.actors.ProcessorBase$$Lambda$4/1107217291.run(Unknown Source)
    at org.apache.activemq.artemis.utils.actors.OrderedExecutor.doTask(OrderedExecutor.java:42)
    at org.apache.activemq.artemis.utils.actors.OrderedExecutor.doTask(OrderedExecutor.java:31)
    at org.apache.activemq.artemis.utils.actors.ProcessorBase.executePendingTasks(ProcessorBase.java:66)
    at org.apache.activemq.artemis.utils.actors.ProcessorBase$$Lambda$4/1107217291.run(Unknown Source)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at org.apache.activemq.artemis.utils.ActiveMQThreadFactory$1.run(ActiveMQThreadFactory.java:118)

    Number of locked synchronizers = 1
    - java.util.concurrent.ThreadPoolExecutor$Worker@1b110644