Hi, In Akka Cluster unreachable and downed are two different things, a node can become unreachable when there is network problems, its JVM is having a long GC pause etc. it may come back from unreachable. Down on the other hand is when a decision has been made about that specific node, that it will never come back and should be removed from the cluster. Cluster singleton will only move the actual singleton when the old node has been downed, as if it reacted on unreachable, the node may still be running and there would be two singleton instances in the cluster.
A node can be marked down manually, using auto-down (which is dangerous because it can lead to "split brain") or using the split brain resolver which is a part of the commercial offerings from Lightbend. You can read more about the options here: * http://doc.akka.io/docs/akka/2.4.8/scala/cluster-usage.html#Automatic_vs__Manual_Downing * https://www.lightbend.com/blog/how-to-handle-network-partitions-decisively-with-akka-split-brain-resolver -- Johan On Sat, Jul 2, 2016 at 1:30 PM, Madabhattula Rajesh Kumar < [email protected]> wrote: > Hi, > > In Akka Cluster Singleton how worker(younger) node receive a message when > Cluster Singleton node(Oldest) was down ? > > In Akka *younger* node I am seeing below WARN message > > *[WARN] [07/02/2016 00:32:55.720] > [ClusterSystem-akka.actor.default-dispatcher-2] > [akka.tcp://ClusterSystem@hostname1:2551/system/cluster/core/daemon] > Cluster Node [akka.tcp://ClusterSystem@hostname1:2551] - Marking node(s) as > UNREACHABLE [Member(address = akka.tcp://ClusterSystem@hostname2:2552, > status = Up)]. Node roles []* > > How to receive this event from younger node. > > > Regards, > Rajesh > > -- > >>>>>>>>>> Read the docs: http://akka.io/docs/ > >>>>>>>>>> Check the FAQ: > http://doc.akka.io/docs/akka/current/additional/faq.html > >>>>>>>>>> Search the archives: https://groups.google.com/group/akka-user > --- > You received this message because you are subscribed to the Google Groups > "Akka User List" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To post to this group, send email to [email protected]. > Visit this group at https://groups.google.com/group/akka-user. > For more options, visit https://groups.google.com/d/optout. > -- >>>>>>>>>> Read the docs: http://akka.io/docs/ >>>>>>>>>> Check the FAQ: >>>>>>>>>> http://doc.akka.io/docs/akka/current/additional/faq.html >>>>>>>>>> Search the archives: https://groups.google.com/group/akka-user --- You received this message because you are subscribed to the Google Groups "Akka User List" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/akka-user. For more options, visit https://groups.google.com/d/optout.
