[
https://issues.apache.org/jira/browse/KARAF-852?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Jean-Baptiste Onofré resolved KARAF-852.
----------------------------------------
Resolution: Cannot Reproduce
Assignee: Jean-Baptiste Onofré
With the latest change (and the storage of the groups in ConfigAdmin), I was
not able to reproduce this issue.
> Cellar node registrations can be lost for groups and distributed service
> endpoints.
> -----------------------------------------------------------------------------------
>
> Key: KARAF-852
> URL: https://issues.apache.org/jira/browse/KARAF-852
> Project: Karaf
> Issue Type: Bug
> Components: cellar-core
> Affects Versions: cellar-2.2.2, cellar-2.2.1
> Reporter: Ioannis Canellos
> Assignee: Jean-Baptiste Onofré
>
> Groups are stored in a distributed collection. Each group object keeps
> internally a set of members (the nodes that are registered to the group). If
> a group is registered simultaneously by two or more nodes, the group object
> will be overwritten. The result will be that the members that were registered
> in the object that was overwritten will be lost.
> Exactly the same issue can occur with nodes registering for remote services.
> Please note, that this is also a problem when two clusters are getting merged.
> This issue will probably never trigger when instances are started manually or
> on relatively small size clusters, but its a problem in cloud deployments of
> 10+ nodes.
> One solution would be to use a distributed lock before accessing these
> collections, but this won't solve the case of the clusters that merge.
> The alternative solution would be to refactor cellar and keep node
> registrations in separate collections. So instead of having a collection of
> groups and keep nodes inside the Group object, we could have a collection of
> group and a multimap of nodes (the key will be the the name and the value
> will be the nodes). We will need to check first how hazelcast multi map merge
> is handled by Hazelcast. If upon muti map merges the value objects are
> overriden instead of appended we will have to work this out the other way
> around. By other way around I mean having the groups & dist. services as part
> of the node.
--
This message was sent by Atlassian JIRA
(v6.2#6252)
