# Clustering

Several Liberators can be configured into a cluster.

A cluster enables a group of Liberators to act as one, in order to monitor licence use and the numbers of users logged on. Client applications can also [publish data](liberator-client-publication.md) to a cluster, for example when using the [chat](../streamlink/streamlink-streamlink-data-types.md) facility, so the data’s available to other clients that use Liberators in the cluster.

## Cluster heartbeats

The Liberators forming a cluster exchange heartbeat messages at regular intervals, allowing each of them to check that all the others are still present. If a Liberator’s cluster heartbeat times out, it waits a configurable time and then disconnects from the cluster and tries to reconnect to it. For more about this, see [`cluster-heartbeat-time`](liberator-clustering-configuration.md#cluster-heartbeat-time) and [`cluster-heartbeat-slack-time`](liberator-clustering-configuration.md#cluster-heartbeat-slack-time) in [Liberator Clustering configuration](liberator-clustering-configuration.md)

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**See also:**

* How can I... [Set up a cluster of Liberators](liberator-set-up-a-cluster-of-liberators.md)
* Reference: [Clustering configuration](liberator-clustering-configuration.md)