1. Cluster State
原文链接 : https://www.elastic.co/guide/en/elasticsearch/reference/5.0/cluster-state.html
译文链接 : http://www.apache.wiki/display/Elasticsearch/Cluster+State
贡献者 : 那伊抹微笑
cluster state（集群状态）API 可以获取一个整个集群更全面的状态。
$ curl -XGET 'http://localhost:9200/_cluster/state'
默认情况下，该集群状态的请求被路由到 Master（主）节点，以确保最近的集群状态可以被返回。出于调试的目的，您可以去指定的本地节点通过添加 local=true 到查询字符串中获取集群状态。
1.1. Response Filters（响应过滤）
由于集群状态可以增加（取决于分片和索引的数量，映射，模版），可能需要过滤集群状态的响应，在 URL 中指定部分参数。
$ curl -XGET 'http://localhost:9200/_cluster/state/{metrics}/{indices}'
| 参数 | 描述 |
|---|---|
| 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 |
几个示例如下 :
# return only metadata and routing_table data for specified indices
$ curl -XGET 'http://localhost:9200/_cluster/state/metadata,routing_table/foo,bar'
# return everything for these two indices
$ curl -XGET 'http://localhost:9200/_cluster/state/_all/foo,bar'
# Return only blocks data
$ curl -XGET 'http://localhost:9200/_cluster/state/blocks'