Cluster State

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The cluster state API allows to get a comprehensive state information of the whole cluster.

GET /_cluster/state

The response provides the cluster name, the total compressed size of the cluster state (its size when serialized for transmission over the network), and the cluster state itself, which can be filtered to only retrieve the parts of interest, as described below.

The cluster’s cluster_uuid is also returned as part of the top-level response, in addition to the metadata section. [6.4.0] Added in 6.4.0.

While the cluster is still forming, it is possible for the cluster_uuid to be _na_ as well as the cluster state’s version to be -1.

By default, the cluster state request is routed to the master node, to ensure that the latest cluster state is returned. For debugging purposes, you can retrieve the cluster state local to a particular node by adding local=true to the query string.

Response Filters

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As the cluster state can grow (depending on the number of shards and indices, your mapping, templates), it is possible to filter the cluster state response specifying the parts in the URL.

GET /_cluster/state/{metrics}/{indices}

metrics can be a comma-separated list of

version
Shows the cluster state version.
master_node
Shows the elected master_node part of the response
nodes
Shows the 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 indices listed.
metadata
Shows the metadata part of the response. If you supply a comma separated list of indices, the returned output will only contain the indices listed.
blocks
Shows the blocks part of the response

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

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

The next example returns everything for the foo and bar indices:

GET /_cluster/state/_all/foo,bar

And this example return only blocks data:

GET /_cluster/state/blocks