Something like downing all members if there's no quorum? I was thinking about that, but there are two problems: - under the current cluster specification, is there a way to resurrect a node? Wouldn't "smarter downing" require you to add a new state, something like "suspended" (waiting for enough members to be in the same state)? - wouldn't this be too global? a per-singleton setting doesn't impact the cluster as a whole, you can have in a single cluster some services which require a quorum, and others which can operate even in a split brain scenario
If I get some free time I'd be happy to work on the issue, I assume master is a good starting point? Adam On Friday, January 2, 2015 3:58:37 PM UTC+1, Patrik Nordwall wrote: > > Hi Adam, > > We have been thinking that this should be handled with a "smarter" downing > strategy, but since it would be easy to implement it in the singleton > manager as you propose I think we should consider it. It has already been > requested in issue: https://github.com/akka/akka/issues/16535 > > Cheers, > Patrik > > On Tue, Dec 30, 2014 at 1:07 PM, Adam Warski <[email protected] > <javascript:>> wrote: > >> Hello, >> >> I was wondering how to avoid split-brain issues when using a cluster >> singleton and automatic downing. >> Wouldn't it make sense to add a "min-nr-of-members" setting to the >> singleton? That is, the singleton wouldn't start unless there's a given >> number of members in the cluster online. That would solve the split brain >> problem with singletons. >> >> I know there is the per-role "min-nr-of-members" setting, which impacts >> the startup of the cluster as a whole, and maybe this could be re-used >> (currently if nodes start up, and then some die (leaving a smaller number >> than the setting alive), the singleton starts up anyway). >> >> Adam >> >> -- >> >>>>>>>>>> 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] <javascript:>. >> To post to this group, send email to [email protected] >> <javascript:>. >> Visit this group at http://groups.google.com/group/akka-user. >> For more options, visit https://groups.google.com/d/optout. >> > > > > -- > > Patrik Nordwall > Typesafe <http://typesafe.com/> - Reactive apps on the JVM > Twitter: @patriknw > > -- >>>>>>>>>> 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.
