I am struggling with the same issue. I am using Cluster Sharding and Cluster Singleton. If I have to programmatically move the actors away from the node that is leaving the cluster, how can I do it?
If I kill the actor, it would take time to get up, and it might even get up on the same node. I can see from my logs that when a node calls cluster.leave, the other node is sending HandOverToMe-messages (1). However, I don't know how to wait for the process to finish. cluster.leave does not wait (afaik), and shuts down the cluster-system before the migration is complete. Is this process documented somewhere? Can I send "HandOverToMe" myself? I don't mind the GUI hanging a few seconds if a node goes down unexpected, but I am trying to avoid it during upgrades, maintenance etc. Best regards, Anders 1) From my log: Retry[X], sending HandOverToMe to [None] onsdag 23. oktober 2013 17.39.38 UTC+2 skrev Akka Team følgende: > > Hi Fedor, > > Akka has currently no specific support for handling the handoff—which is > an application-specific concern anyway. In your case the node should do > whatever is necessary to hand off its data and only then initiate the > LEAVING state to finally exit. > > Regards, > > Roland > > On Wednesday, October 23, 2013, Fedor Tokarev wrote: > >> Hi Viktor, >> >> Yeah, when a node is died unexpectedly, data migration is not possible. >> But what if a node is about to be gracefully stopped? What are the ways to >> perform a data migration in this case? >> >> A possible scenario: we have a cluster of N nodes. We shut down one node >> at a time, update its software, then bring it back to the cluster. Data >> should be migrated from a node before the maintenance, and then should be >> returned to the node after the maintenance. >> >> среда, 23 октября 2013 г., 18:41:44 UTC+4 пользователь √ написал: >>> >>> If you get Exited it's already too late. >>> >>> Compare this to a nomber of people out in the forest, communicating over >>> walkie-talkies. >>> If someone goes silent, after a while the others must assume he/she is >>> dead and move on, >>> at that point it's too late for that lost individual to start migrating >>> data (who would he migrate data to?) >>> >>> cheers, >>> √ >>> >>> >>> On Wed, Oct 23, 2013 at 4:29 PM, Fedor Tokarev <[email protected]> >>> wrote: >>> >>>> Hi guys, >>>> >>>> What is the right way to migrate data from a leaving node? The docs say >>>> that ClusterEvent.MemberExited may be received when a node is already >>>> down. >>>> Does it mean that a leaving node must initiate data migration itself? How >>>> a >>>> node can detect that it is about to leave? How to make sure that the >>>> leader >>>> won't shutdown a leaving node in the middle of the data migration process? >>>> >>>> -- >>>> >>>>>>>>>> Read the docs: http://akka.io/docs/ >>>> >>>>>>>>>> Check the FAQ: http://akka.io/faq/ >>>> >>>>>>>>>> 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 http://groups.google.com/group/akka-user. >>>> For more options, visit https://groups.google.com/groups/opt_out. >>>> >>> >>> >>> >>> -- >>> Cheers, >>> √ >>> >>> * Viktor Klang* >>> *Director of Engineering* >>> Typesafe <http://www.typesafe.com/> >>> >>> Twitter: @viktorklang >>> >> -- >> >>>>>>>>>> Read the docs: http://akka.io/docs/ >> >>>>>>>>>> Check the FAQ: http://akka.io/faq/ >> >>>>>>>>>> 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 http://groups.google.com/group/akka-user. >> For more options, visit https://groups.google.com/groups/opt_out. >> > > > -- > Akka Team > Typesafe - The software stack for applications that scale > Blog: letitcrash.com > Twitter: @akkateam > > -- >>>>>>>>>> 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 http://groups.google.com/group/akka-user. For more options, visit https://groups.google.com/d/optout.
