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From Jean-Baptiste Onofré ...@nanthrax.net>
Subject Re: Cellar groups usage
Date Thu, 25 Jan 2018 09:30:52 GMT
Hi Thomas,

did you move the nodes to default to groupA ?

If nodes belong to multiple groups, it's the expected behavior.

Union of groups is not a good setup as you can have slight difference.
That's why you have the cluster:group-move/set.

Regards
JB

On 01/25/2018 10:21 AM, Thomas Draier wrote:
> Hi,
> 
> We have been trying to use cellar groups for our cluster deployments. The
> idea was to be able to deploy one bundle to only a subset of nodes, but
> actually we did not manage to make it work.
> 
> We created one single group, say groupA that contains 2 nodes, in addition
> to the default group, which contain all nodes. Both groups use the
> "cluster" configuration (pull / push), bundles can be handled by any group
> (no whitelist/blacklist), and no local listener is configured.
> 
> Basically, when we deploy a module on groupA, the module is correctly
> installed on all nodes of this group, and everything goes fine. However, if
> a sync is done on the default group, the bundle will be immediately
> uninstalled, as the "pull" operation will see this bundle as local only
> (it's not in default group) and will uninstall it.
> 
> On the other hand, if we deploy a module on default group, it's correctly
> installed everywhere, but the next sync of groupA will uninstall the bundle
> from the 2 nodes that it owns.
> 
> Since sync are done automatically quite often, including at startup, some
> bundles can get unexpectedly uninstalled at any time. At startup, since all
> groups are syncing in a random order - the last group to sync will "win",
> so will reinstall bundles that were just uninstalled by the previous sync -
> but bundles only installed on other groups will be removed.
> 
> We were thinking of different possible fixes for handling that ( maybe
> changing the sync, checking that the bundle is not part of any cluster
> group before uninstalling it or changing its state ), but it's actually not
> quite clear what is the expected behaviour and how it is supposed to work.
> Is there anything wrong in the way we are using groups ?
> 
> Thomas
> 

-- 
Jean-Baptiste Onofré
jbonofre@apache.org
http://blog.nanthrax.net
Talend - http://www.talend.com

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