A common operation will be telling the client what nodes are in your cluster. By default, the client will connect to localhost:9200, which obviously doesn’t work in many production environments.

All configurations (both simple parameters and more advanced component-replacement) are injected into the constructor of the client.

The client accepts an array of hosts that you would like to connect to. Each value in the array must be a string (either with or without the port number):

$params = array();
$params['hosts'] = array (
    '192.168.1.1:9200',         // IP + Port
    '192.168.1.2',              // Just IP
    'mydomain.server.com:9201', // Domain + Port
    'mydomain2.server.com'      // Just Domain
);

$client = new Elasticsearch\Client($params);

This associative array holds all custom configurations that you may want to set. Often, you’ll only need to configure the hosts, but if you need more advanced behavior, read on.