Modules

This section contains modules responsible for various aspects of the functionality in Elasticsearch. Each module has settings which may be:

static: These settings must be set at the node level, either in the elasticsearch.yml file, or as an environment variable or on the command line when starting a node. They must be set on every relevant node in the cluster.
dynamic: These settings can be dynamically updated on a live cluster with the cluster-update-settings API.

The modules in this section are:

Discovery and cluster formation: How nodes discover each other, elect a master and form a cluster.
Shard allocation and cluster-level routing: Settings to control where, when, and how shards are allocated to nodes.
Gateway: How many nodes need to join the cluster before recovery can start.
HTTP: Settings to control the HTTP REST interface.
Indices: Global index-related settings.
Network: Controls default network settings.
Node client: A Java node client joins the cluster, but doesn’t hold data or act as a master node.
Painless: A built-in scripting language for Elasticsearch that’s designed to be as secure as possible.
Plugins: Using plugins to extend Elasticsearch.
Scripting: Custom scripting available in Lucene Expressions, ad Groovy. You can also write scripts in the built-in scripting language, Painless.
Snapshot/Restore: Backup your data with snapshot/restore.
Thread pools: Information about the dedicated thread pools used in Elasticsearch.
Transport: Configure the transport networking layer, used internally by Elasticsearch to communicate between nodes.
Remote clusters: Remote clusters are used in features that work by connecting across clusters on the transport layer.
Cross-cluster search: Cross-cluster search enables executing search requests across more than one cluster without joining them and acts as a federated client across them.