gistfile1.php

<?php defined('SYSPATH')or die('No access');

class Controller_Sites extends Controller_Template {

   public function action_index()
   {
      $sites = ORM::factory('site')->sites()->find_all();
   }

}

sites_model.php

<?php defined('SYSPATH')or die('No access');

class Model_Site extends ORM {

   protected $_has_many = array(
      'servers' => array(
         'model'       => 'server',
         'far_key'     => 'id',
         'foreign_key' => 'server_id'
      )
   );

   private $server_id = 0;

   public $ip = '0.0.0.0';

   public function factory($model, $id = NULL)
   {
      $this->ip = shell_exec('host $this->name | grep address | awk \'{printf $4}\'');

      parent::factory($model, $id);
   }

   public function sites()
   {
      $this->where('server_id', '=', $this->server_id);

      return $this;
   }

}