[[discovery-multicast]]
=== Multicast Discovery Plugin

The Multicast Discovery plugin provides the ability to form a cluster using
TCP/IP multicast messages.

[[discovery-multicast-install]]
[float]
==== Installation

This plugin can be installed using the plugin manager:

[source,sh]
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sudo bin/plugin install discovery-multicast
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The plugin must be installed on every node in the cluster, and each node must
be restarted after installation.

[[discovery-multicast-remove]]
[float]
==== Removal

The plugin can be removed with the following command:

[source,sh]
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sudo bin/plugin remove discovery-multicast
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The node must be stopped before removing the plugin.

[[discovery-multicast-usage]]
==== Configuring multicast discovery

Multicast ping discovery of other nodes is done by sending one or more
multicast requests which existing nodes will receive and
respond to. It provides the following settings with the
`discovery.zen.ping.multicast` prefix:

[cols="<,<",options="header",]
|=======================================================================
|Setting |Description
|`group` |The group address to use. Defaults to `224.2.2.4`.

|`port` |The port to use. Defaults to `54328`.

|`ttl` |The ttl of the multicast message. Defaults to `3`.

|`address` |The address to bind to, defaults to `null` which means it
will bind `network.bind_host`

|`enabled` |Whether multicast ping discovery is enabled. Defaults to `false`.
|=======================================================================