GitHub user nmalonzo added a comment to the discussion: Akka to Pekko Migration Rollback
Thanks. Pardon me if I clarify some things. The wiki says join Pekko nodes to an Akka cluster. Do you mean starting Pekko nodes while Akka nodes are still alive? The Akka node cluster coordinator will detect these pekko nodes and treat them as akka nodes? When all akka nodes are terminated the cluster coordinator will be transferred to a pekko node pretending to be an akka node. At this point it is still an Akka cluster? Once all Akka pretending pekko nodes have been configured as Pekko nodes then it will be a Pekko cluster? So while rolling deployment is happening to change these nodes one by one to Pekko nodes presenting as Pekko nodes, two clusters will exist? An akka cluster and a pekko cluster? A persistent entity on a node migrated to Pekko is not guaranteed to be able to be rolled back to Akka right? A pekko node pretending to be an Akka node can change the journal/snapshot such that it cannot be loaded to an Akka node? So coupled with the lack of guarantee in Akka Pekko persistence (even with a freezed Pekko version) the safe way to migrate from Akka to Pekko is to maintain a separate Akka and Pekko cluster while migration is ongoing. The problem with this is we have to deploy a GRPC endpoint to the persistent state nodes to be able to communicate with the other cluster. But with no guarantee of roll back to Akka can be done even with Akka Pekko coexistence it is the only choice. GitHub link: https://github.com/apache/pekko/discussions/1421#discussioncomment-10252251 ---- This is an automatically sent email for [email protected]. To unsubscribe, please send an email to: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
