Chapter 4. Cluster Groups
Until now, we have used Cellar as a global cluster. This means that all the nodes will have the same functions and roles in the cluster. However, when using a pool or farm of Karaf instances in a real live system, we may want to dedicate a subset of the instances for the given functions/roles. This is the role of the Cellar cluster groups.
For instance, we have a farm of 20 nodes in our Cellar cluster.
We may want to deploy the following:
- A camel route can be described and packaged as a
Karaf Features
XML file. We want to deploy this route only on 10 nodes of the cluster (not on all the nodes). - A CXF web service (described and deployed as another
Karaf Features
XML file) on the other 10 nodes.
In Cellar, we can create different cluster groups and define a node as a member of one or more cluster groups.