Use IP and 'peer_name' => 'ssl://smtp.mailgun.org' to workaround mailgun connection timeout issues

<?php
    $remote_socket = 'ssl://34.160.13.42:465';

    // Set ssl context options, see http://php.net/manual/en/context.ssl.php
    $options['ssl'] = array('peer_name' => 'ssl://smtp.mailgun.org', 'verify_peer' => true, 'verify_peer_name' => true, 'allow_self_signed' => false);
    $socket_context = stream_context_create($options);

    $socket = @stream_socket_client($remote_socket, $errno, $errstr, 20, STREAM_CLIENT_CONNECT, $socket_context);

    if (!$socket)
    {
        echo $errno.' '.$errstr."\n";
        return;
    }

    $server_response = fgets($socket, 256);
    echo $server_response;

    fclose($socket);
?>