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= Cluster Groups

:javaFile: {javaCodeDir}/ClusterAPI.java

The `ClusterGroup` interface represents a logical group of nodes, which can be used in many of Ignite's APIs when you want to limit the scope of specific operations to a subset of nodes (instead of the whole cluster). For example, you may wish to deploy a service only on remote nodes or execute a job only on the set of nodes that have a specific attribute.
////
TODO: explain attributes
////
TIP: Note that the `IgniteCluster` interface is also a cluster group which includes all the nodes in the cluster.

You can limit job execution, service deployment, messaging, events, and
other tasks to run only on a specific set of node. For example, here is
how to broadcast a job only to remote nodes (excluding the local node).

[tabs]
--
tab:Java[]
[source,java]
----
include::{javaFile}[tag=remote-nodes,indent=0]
----
tab:C#/.NET[]
[source,csharp]
----
include::code-snippets/dotnet/ClusterGroups.cs[tag=broadcastAction,indent=0]
----
tab:C++[]
[source,cpp]
----
include::code-snippets/cpp/src/broadcast_jobs_to_remote_nodes.cpp[tag=remote-nodes,indent=0]
----
--


For convenience, Ignite comes with a number of predefined cluster groups.


[tabs]
--
tab:Java[]
[source,java]
----
include::{javaFile}[tag=group-examples,indent=0]
----
tab:C#/.NET[]
[source,csharp]
----
include::code-snippets/dotnet/ClusterGroups.cs[tag=clusterGroups,indent=0]
----
tab:C++[]
[source,cpp]
----
include::code-snippets/cpp/src/predefined_cluster_groups.cpp[tag=cluster-groups,indent=0]
----
--