[[cluster-update-settings]]
== Cluster Update Settings

Allows to update cluster wide specific settings. Settings updated can
either be persistent (applied cross restarts) or transient (will not
survive a full cluster restart). Here is an example:

[source,js]
--------------------------------------------------
curl -XPUT localhost:9200/_cluster/settings -d '{
    "persistent" : {
        "discovery.zen.minimum_master_nodes" : 2
    }
}'
--------------------------------------------------

Or:

[source,js]
--------------------------------------------------
curl -XPUT localhost:9200/_cluster/settings -d '{
    "transient" : {
        "discovery.zen.minimum_master_nodes" : 2
    }
}'
--------------------------------------------------

The cluster responds with the settings updated. So the response for the
last example will be:

[source,js]
--------------------------------------------------
{
    "persistent" : {},
    "transient" : {
        "discovery.zen.minimum_master_nodes" : "2"
    }
}'
--------------------------------------------------

Cluster wide settings can be returned using:

[source,js]
--------------------------------------------------
curl -XGET localhost:9200/_cluster/settings
--------------------------------------------------


A list of dynamically updatable settings can be found in the
<<modules,Modules>> documentation.