[[discovery]]
== Discovery Plugins

Discovery plugins extend Elasticsearch by adding new seed hosts providers that
can be used to extend the {ref}/modules-discovery.html[cluster formation
module].

[discrete]
==== Core discovery plugins

The core discovery plugins are:

<<discovery-ec2,EC2 discovery>>::

The EC2 discovery plugin uses the https://github.com/aws/aws-sdk-java[AWS API]
to identify the addresses of seed hosts.

<<discovery-azure-classic,Azure Classic discovery>>::

The Azure Classic discovery plugin uses the Azure Classic API to identify the
addresses of seed hosts.

<<discovery-gce,GCE discovery>>::

The Google Compute Engine discovery plugin uses the GCE API to identify the
addresses of seed hosts.

include::discovery-ec2.asciidoc[]

include::discovery-azure-classic.asciidoc[]

include::discovery-gce.asciidoc[]