Cluster state API

Cluster state API

Returns an internal representation of the cluster state for debugging or diagnostic purposes.

Request

GET /_cluster/state/<metrics>/<target>

Prerequisites

  • If the Elasticsearch security features are enabled, you must have the monitor or manage cluster privilege to use this API.

Description

The cluster state is an internal data structure which keeps track of a variety of information needed by every node, including:

  • The identity and attributes of the other nodes in the cluster
  • Cluster-wide settings
  • Index metadata, including the mapping and settings for each index
  • The location and status of every shard copy in the cluster

The elected master node ensures that every node in the cluster has a copy of the same cluster state. The cluster state API lets you retrieve a representation of this internal state for debugging or diagnostic purposes. You may need to consult the Elasticsearch source code to determine the precise meaning of the response.

By default the cluster state API will route requests to the elected master node since this node is the authoritative source of cluster states. You can also retrieve the cluster state held on the node handling the API request by adding the query parameter ?local=true.

Elasticsearch may need to expend significant effort to compute a response to this API in larger clusters, and the response may comprise a very large quantity of data. If you use this API repeatedly, your cluster may become unstable.

The response is a representation of an internal data structure. Its format is not subject to the same compatibility guarantees as other more stable APIs and may change from version to version. Do not query this API using external monitoring tools. Instead, obtain the information you require using other more stable cluster APIs.

Path parameters

The cluster state can sometimes be very large, and Elasticsearch may consume significant resources while computing a response to this API. To reduce the size of the response, you can request only the part of the cluster state in which you are interested:

<metrics>

(Optional, string) A comma-separated list of the following options:

  • _all

    Shows all metrics.

    blocks

    Shows the blocks part of the response.

    master_node

    Shows the master_node part of the response.

    metadata

    Shows the metadata part of the response. If you supply a comma separated list of indices, the returned output will only contain metadata for these indices.

    nodes

    Shows the nodes part of the response.

    routing_nodes

    Shows the routing_nodes part of the response.

    routing_table

    Shows the routing_table part of the response. If you supply a comma separated list of indices, the returned output will only contain the routing table for these indices.

    version

    Shows the cluster state version.

<target>

(Optional, string) Comma-separated list of data streams, indices, and aliases used to limit the request. Supports wildcards (*). To target all data streams and indices, omit this parameter or use * or _all.

Query parameters

allow_no_indices

(Optional, Boolean) If true, the wildcard indices expression that resolves into no concrete indices will be ignored. (This includes _all string or when no indices have been specified).

Defaults to true.

expand_wildcards

(Optional, string) Whether to expand wildcard expression to concrete indices that are open, closed or both. Available options: open, closed, none, all.

flat_settings

(Optional, Boolean) If true, returns settings in flat format. Defaults to false.

ignore_unavailable

(Optional, Boolean) If true, unavailable indices (missing or closed) will be ignored.

local

(Optional, Boolean) If true, the request retrieves information from the local node only. Defaults to false, which means information is retrieved from the master node.

master_timeout

(Optional, time units) Period to wait for a connection to the master node. If no response is received before the timeout expires, the request fails and returns an error. Defaults to 30s.

wait_for_metadata_version

(Optional, integer) Waits for the metadata version to be equal or greater than the specified metadata version.

wait_for_timeout

(Optional, time units) Specifies the maximum time to wait for wait_for_metadata_version before timing out.

Examples

The following example returns only metadata and routing_table data for the foo and bar data streams or indices:

  1. GET /_cluster/state/metadata,routing_table/foo,bar

The next example returns all available metadata for foo and bar:

  1. GET /_cluster/state/_all/foo,bar

This example returns only the blocks metadata:

  1. GET /_cluster/state/blocks