Elastic Search Give an error No alive nodes found in your cluster

I am start working with elastic search.I successfully install elastic search on my server(Different from application server).But When I try to call Elatic search from my Application server it gives an error
Fatal error: Uncaught exception 'Elasticsearch\Common\Exceptions\NoNodesAvailableException' with message 'No alive nodes found in your cluster'

When I check Elastic search status it shows Active.

How can I call elastic search from my Application server to my Elastic search server.

<?php
    require 'vendor/autoload.php';
    $hosts = [
       'ip_address:9200'         // IP + Port
    ];
    $client = Elasticsearch\ClientBuilder::create()->setHosts($hosts)->build();

    $params = [
        'index' => 'my_index',
        'type' => 'my_type',
        'id' => 'my_id',
        'body' => ['testField' => 'abc']
    ];

    $response = $client->index($params);
?>

My elasticsearch.yml Settings

    # ======================== Elasticsearch Configuration =========================
    #
    # NOTE: Elasticsearch comes with reasonable defaults for most settings.
    #       Before you set out to tweak and tune the configuration, make sure you
    #       understand what are you trying to accomplish and the consequences.
    #
    # The primary way of configuring a node is via this file. This template lists
    # the most important settings you may want to configure for a production cluster.
    #
    # Please see the documentation for further information on configuration options:
    # <http://www.elastic.co/guide/en/elasticsearch/reference/current/setup-configuration.html>
    #
    # ---------------------------------- Cluster -----------------------------------
    #
    # Use a descriptive name for your cluster:
    #
     cluster.name: my-application
    #
    # ------------------------------------ Node ------------------------------------
    #
    # Use a descriptive name for the node:
    #
     node.name: node-1
    #
    # Add custom attributes to the node:
    #
    # node.rack: r1
    #
    # ----------------------------------- Paths ------------------------------------
    #
    # Path to directory where to store the data (separate multiple locations by comma):
    #
    # path.data: /path/to/data
    #
    # Path to log files:
    #
    # path.logs: /path/to/logs
    #
    # ----------------------------------- Memory -----------------------------------
    #
    # Lock the memory on startup:
    #
    # bootstrap.memory_lock: true
    #
    # Make sure that the `ES_HEAP_SIZE` environment variable is set to about half the memory
    # available on the system and that the owner of the process is allowed to use this limit.
    #
    # Elasticsearch performs poorly when the system is swapping the memory.
    #
    # ---------------------------------- Network -----------------------------------
    #
    # Set the bind address to a specific IP (IPv4 or IPv6):
    #
    #network.host: 0.0.0.0
    #network.bind_host: 0
    #
    # Set a custom port for HTTP:
    #
    # http.port: 9200
    #
    # For more information, see the documentation at:
    # <http://www.elastic.co/guide/en/elasticsearch/reference/current/modules-network.html>
    #
    # --------------------------------- Discovery ----------------------------------
    #
    # Pass an initial list of hosts to perform discovery when new node is started:
    # The default list of hosts is ["127.0.0.1", "[::1]"]
    #
    # discovery.zen.ping.unicast.hosts: ["host1", "host2"]
    #
    # Prevent the "split brain" by configuring the majority of nodes (total number of nodes / 2 + 1):
    #
    # discovery.zen.minimum_master_nodes: 3
    #
    # For more information, see the documentation at:
    # <http://www.elastic.co/guide/en/elasticsearch/reference/current/modules-discovery.html>
    #
    # ---------------------------------- Gateway -----------------------------------
    #
    # Block initial recovery after a full cluster restart until N nodes are started:
    #
    # gateway.recover_after_nodes: 3
    #
    # For more information, see the documentation at:
    # <http://www.elastic.co/guide/en/elasticsearch/reference/current/modules-gateway.html>
    #
    # ---------------------------------- Various -----------------------------------
    #
    # Disable starting multiple nodes on a single system:
    #
    # node.max_local_storage_nodes: 1
    #
    # Require explicit names when deleting indices:
    #
    # action.destructive_requires_name: true

elasticsearch.yml settings which are not working

network.host: 127.0.0.1

network.host: 0

network.host: 0.0.0.0

network.host: IP_Address

network.bind_host: 0

network.bind_host: IP_Address

When I set the above settings then elasticsearch shows the failed status.

NOTE : Elastic search install on different server from my Application sever.