On Fri, Mar 17, 2017 at 7:29 AM, kant kodali <kanth...@gmail.com> wrote:
> Do I need to specify how many nodes or shards I want to distribute to ? > Not by number, but IIRC you can assign particular roles to nodes, and have those roles determine what sorts of things get distributed to those nodes. Note that you *do* implicitly have to pre-decide how many shards to break a given concept down to. But a given node typically hosts a number of shards, and that rebalances dynamically. > Node can go up and down right.. Can the Akka cluster discover how many > nodes are available at any given time? > That's essentially what clustering does, yes. There's an underlying gossip mechanism, so that all nodes have a rough idea of all of the others at any given time. > Also, Why should I manually down the node? I know that there is a failure > detector so if the Akka cluster "thinks" a node is dead then why cant it > simply distribute that region to other actors? > Problem is, there's a lot of judgement call involved in deciding whether a node is just temporarily unavailable due to a network failure or is actually down. Getting this wrong has *serious* consequences, and can lead to data corruption. Akka per se doesn't make that decision, although Lightbend does sell a product named Split Brain Resolver that provides a fairly sophisticated algorithm to make the decision. Basically, Akka doesn't say whether it thinks a node is *down*, it just knows that it is temporarily unavailable. You have to decide when that actually means "down". -- >>>>>>>>>> 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 akka-user+unsubscr...@googlegroups.com. To post to this group, send email to akka-user@googlegroups.com. Visit this group at https://groups.google.com/group/akka-user. For more options, visit https://groups.google.com/d/optout.
