karaf-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Thomas Draier <tdra...@jahia.com>
Subject Re: Cellar groups usage
Date Thu, 25 Jan 2018 10:10:25 GMT
I will go back to #44 then :-)

Yes, we are using a fork with changes from #44. And also some other changes
in the synchronizers - we are currently reviewing if there are still things
we may need to push to the master or if they have already been fixed.

thomas

On Thu, Jan 25, 2018 at 11:02 AM Jean-Baptiste Onofré <jb@nanthrax.net>
wrote:

> That's bad: a node can leave the default group.
>
> I didn't approve https://github.com/apache/karaf-cellar/pull/44 yet,
> especially
> because it changes the group management. That's why I would like to do a
> deep
> review ;)
> I guess you are using a fork on Cellar with your changes, right ?
>
> Let me check the sync change I did.
>
> Regards
> JB
>
> On 01/25/2018 10:57 AM, Thomas Draier wrote:
> > Hi JB,
> >
> > I did not move the node to groupA, as all groups always belong to default
> > and we cannot "leave" default group (or should they not ? maybe I broke
> > this in https://github.com/apache/karaf-cellar/pull/44 ? ). In our case
> we
> > need to have nodes belong to multiple groups - we have a "limited" group
> > for deploying bundles only on a sub set of nodes, but deployment on
> default
> > should still deploy on all nodes.
> >
> > We are on a quite old version of cellar ( karaf 4.0.7 / cellar 4.0.2 ),
> can
> > you point me to the changes on sync you are talking ? We can probably
> > upgrade cellar but upgrading karaf will be more difficult, is is possible
> > to cellar 4.1.x on karaf 4.0.7 ?
> >
> > Thanks !
> >
> > On Thu, Jan 25, 2018 at 10:30 AM Jean-Baptiste Onofré <jb@nanthrax.net>
> > wrote:
> >
> >> 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
> >>
> >
>
> --
> Jean-Baptiste Onofré
> jbonofre@apache.org
> http://blog.nanthrax.net
> Talend - http://www.talend.com
>

Mime
  • Unnamed multipart/alternative (inline, None, 0 bytes)
View raw message