Get cluster-wide settings

If true, returns settings in flat format.

If true, also returns the values of all other cluster settings set in the elasticsearch.yml file on one of the nodes in your cluster, together with the default values of all other cluster settings on that node. The default value of each setting may depend on the values of other settings on that node. If the nodes in your cluster do not all have the same configuration then the values returned by this API may vary from invocation to invocation and may not reflect the values that Elasticsearch uses in all situations. Use the GET _nodes/settings API to fetch the settings for each individual node in your cluster.

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.