Hi everyone, We are trying to achieve "at-least-once" delivery with cluster sharding and persistent actor.
Context: *ActorSystemA*: - PersistentActorA *ActorSystemB*: - ActorB PersistentActorA receives a message, persist it, then send it to ActorB. Once ActorB processed it, it sends back an ACK to PersistentActorA which then uses *confirmDelivery*. Works like a charm in a non-cluster situation. Just one JVM to another with akka-remote, PersistentActorA has a fixed persistenceId. Now we want to scale this situation. Multiple *ActorSystemA* are running at the same time, part of the same cluster. Now we have to use sharding to make sure there is only one *PersistentActorA *instance in the cluster for the same entity id. Problem appears when we start scaling because of the characteristic of our payload. It's a one-off payload. The ID inside, used to compute the entity ID for sharding, it's not an ID which will appear again in another message. That means, if for whatever reason this scenario happens: 1. message is persisted by the *PersistentActorA *for a particular entity ID (let's say the ID is 1) 2. message can't be sent (ActorSystemB is down) 3. The *PersistentActorA *for the entity ID 1 is going down (crashed application...) Because there won't be any other payload with entity ID == 1, this *PersistentActorA* will never be created again. So, the messages won't be replayed form the journal, and the message will never get delivered. Am I right? Or we are missing something? Thanks for your help, -- >>>>>>>>>> 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.
