Cluster State
editCluster State
editThe cluster state API allows access to metadata representing the state of the whole cluster. This includes information such as
- the set of nodes in the cluster
- all cluster-level settings
- information about the indices in the cluster, including their mappings and settings
- the locations of all the shards in the cluster
The response is an internal representation of the cluster state and its format may change from version to version. If possible, you should obtain any information from the cluster state using the other, more stable, cluster APIs.
GET /_cluster/state
The response provides 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
editThe cluster state contains information about all the indices in the cluster, including their mappings, as well as templates and other metadata. This means it can sometimes be quite large. To avoid the need to process all this information you can request only the part of the cluster state that you need:
GET /_cluster/state/{metrics} GET /_cluster/state/{metrics}/{indices}
{metrics}
is a comma-separated list of the following options.
-
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 routing table for these indices. -
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. -
blocks
-
Shows the
blocks
part of the response. -
_all
- Shows all metrics.
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
Finally, this example return only the blocks
metadata:
GET /_cluster/state/blocks