Create two table for example user and admin ¶

login links will be

youdomain.com/index.php?r=site/site/login

make a copy of site/login.php and name it as AdminLogin.php

youdomain.com/index.php?r=site/AdminLogin

CREATE TABLE IF NOT EXISTS `tbl_user` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `username` varchar(128) NOT NULL,
  `password` varchar(128) NOT NULL,
  `salt` varchar(128) NOT NULL,
  `first_name` varchar(200) NOT NULL,
  `last_name` varchar(200) NOT NULL,
  `email` varchar(128) NOT NULL,
  `profile` int(11) DEFAULT '0',
  `photo` varchar(120) DEFAULT NULL,
  `status` int(11) NOT NULL,
  PRIMARY KEY (`id`)
)

CREATE TABLE IF NOT EXISTS `tbl_admin` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `username` varchar(128) NOT NULL,
  `password` varchar(128) NOT NULL,
  `salt` varchar(128) NOT NULL,
  `first_name` varchar(200) NOT NULL,
  `last_name` varchar(200) NOT NULL,
  `email` varchar(128) NOT NULL,
  `admin_name` varchar(128) NOT NULL,
  `admin_type` varchar(128) NOT NULL,
  `profile` int(11) DEFAULT '1',
  `status` int(11) NOT NULL,
  PRIMARY KEY (`id`)
)

While creating users make sure profile value should pass hidden value 1 for admin and 0 for user ¶

in controller/SiteController.php

public function actionLogin()
	{
		$model=new LoginForm;

		// if it is ajax validation request
		if(isset($_POST['ajax']) && $_POST['ajax']==='login-form')
		{
			echo CActiveForm::validate($model);
			Yii::app()->end();
		}

		// collect user input data
		if(isset($_POST['LoginForm']))
		{
			$model->attributes=$_POST['LoginForm'];
			// validate user input and redirect to the previous page if valid
			if($model->validate() && $model->login())
				 $this->redirect('index.php?r=user/dashboard');
		}
		// display the login form
		$this->render('login',array('model'=>$model));
	}
	public function actionAdminLogin()
	{
		$model=new LoginForm;

		// if it is ajax validation request
		if(isset($_POST['ajax']) && $_POST['ajax']==='login-form')
		{
			echo CActiveForm::validate($model);
			Yii::app()->end();
		}

		// collect user input data
		if(isset($_POST['LoginForm']))
		{
			$model->attributes=$_POST['LoginForm'];
			// validate user input and redirect to the previous page if valid
			if($model->validate() && $model->login1())
				if(Yii::app()->user->profile==1)
				{
					 $this->redirect('index.php?r=admin/dashboard');
				}
				else{
					 $this->redirect('index.php?r=user/dashboard');
				}
		}
		// display the login form
		$this->render('login',array('model'=>$model));
	}

on models/LoginForm.php

public function authenticate($attribute,$params)
	{

		if(!$this->hasErrors())
		{
			$this->_identity=new UserIdentity($this->username,$this->password);
			if(!$this->_identity->authenticate())
				$this->addError('password','Incorrect username or password.');
		}
	}
	public function authenticate1($attribute,$params)
	{

		if(!$this->hasErrors())
		{
			$this->_identity=new UserIdentity($this->username,$this->password);
			if(!$this->_identity->authenticate())
				$this->addError('password','Incorrect username or password.');
		}
	}

	/**
	 * Logs in the user using the given username and password in the model.
	 * @return boolean whether login is successful
	 */
	public function login()
	{
		if($this->_identity===null)
		{
			$this->_identity=new UserIdentity($this->username,$this->password);
			if(!$this->_identity->authenticate())
				$this->addError('password','Incorrect username or password.');
		}
		if($this->_identity->errorCode===UserIdentity::ERROR_NONE)
		{
			$duration=$this->rememberMe ? 3600*24*30 : 0; // 30 days
			Yii::app()->user->login($this->_identity,$duration);
			return true;
		}
		else
			return false;
	}
	public function login1()
	{
		if($this->_identity===null)
		{
			
			$this->_identity=new UserIdentity($this->username,$this->password);
			if(!$this->_identity->authenticate1())
				$this->addError('password','Incorrect username or password.');
		}
		if($this->_identity->errorCode===UserIdentity::ERROR_NONE)
		{
			$duration=$this->rememberMe ? 3600*24*30 : 0; // 30 days
			Yii::app()->user->login($this->_identity,$duration);
			return true;
		}
		else
			return false;
	}

components/UserIdentity.php

public function authenticate()
	{

		//$user=User::model()->find('LOWER(username)=?',array(strtolower($this->username)));
		$user=User::model()->findByAttributes(array('username'=>strtolower($this->username),'status'=>1));
		if($user===null)
			$this->errorCode=self::ERROR_USERNAME_INVALID;
		else if(!$user->validatePassword($this->password))
			$this->errorCode=self::ERROR_PASSWORD_INVALID;
		else
		{
			$this->_id=$user->id;
			$this->username=$user->username;
			 $this->setState('profile', $user->profile);
			$this->errorCode=self::ERROR_NONE;
		}
		return $this->errorCode==self::ERROR_NONE;
	}
	public function authenticate1()
	{
		$user=Admin::model()->findByAttributes(array('username'=>strtolower($this->username),'status'=>1));
		if($user===null)
			$this->errorCode=self::ERROR_USERNAME_INVALID;
		else if(!$user->validatePassword($this->password))
			$this->errorCode=self::ERROR_PASSWORD_INVALID;
		else
		{
			$this->_id=$user->id;
			$this->username=$user->username;
			 $this->setState('profile', $user->profile);
			$this->errorCode=self::ERROR_NONE;
		}
		return $this->errorCode==self::ERROR_NONE;
	}

Thanks Balu