Login frontend dan backend codeigniter dalam 1 browser

ASK, dalam 1 aplikasi codeigniter saya terdapat 2 login yaitu untuk backend dan frontend, tetapi ketika saya login ke backend, kemudian kembali login dibagian frontend dalam 1 browser yang sama. pada bagian backend langsung ke logout/ malah error.

begitu pula jika saya login bagian frontend terlebih dahulu, lalu kemudian login pada bagian backend.

apakah bisa dalam 1 browser, login backend dan frontend tersebut terbuka secara bersamaan.

Berikut skript yang ane pakai.

/// Login Admin
	public function login()
	{

			$config = array(

               array(
                     'field'   => 'password',
                     'label'   => 'Password',
                     'rules'   => 'required|trim|xss_clean'
                  )
            );

			$this->form_validation->set_message($config);
			$this->form_validation->set_rules($config);

			if($this->form_validation->run() == FALSE){

				$this->load->view('login');

			}else{

				extract($_POST);
				$user_id = $this->Alus_user->check_login($username,$password);


					if(! $user_id)
					{

					$this->session->set_flashdata('gagal_masuk',TRUE);
					redirect('panel/login');

					}
					else
					{
					$this->load->model('Alus_user');
					$config = $this->Alus_user->user_info($user_id);
					$data_user = array(
										'masuk' => TRUE,
										'user_id' => $user_id,
										'username' => $config['username'],
										'nama' => $config['nama_user'],
										'level' => $config['level'],
										'lastlogin' => $config['lastlogin']

									   );
					//$this->Alus_user->user_info_update($user_id);
					$this->session->set_userdata($data_user);
					redirect('dashboard');

					}

			}


	}

//Login Member/Frontend
public function login_member()
	{

			$config = array(

               array(
                     'field'   => 'password',
                     'label'   => 'Password',
                     'rules'   => 'required|trim'
                  )
            );

			$this->form_validation->set_message($config);
			$this->form_validation->set_rules($config);

			if($this->form_validation->run() == FALSE){

				$this->load->view('login_member');

			}else{

				extract($_POST);
				$user_id = $this->Alus_member->check_login($username,$password);


					if(! $user_id)
					{

					$this->session->set_flashdata('gagal_masuk',TRUE);
					redirect('panel/login_member');

					}
					else
					{
					$config = $this->Alus_member->member_info($user_id);
					$data_user = array(
										'masuk_member' => TRUE,
										'user_id' => $user_id,
										'username' => $config['username'],
										'nama' => $config['name']
									   );
					//$this->Alus_user->user_info_update($user_id);
					$this->session->set_userdata($data_user);
					redirect('front/member');

					}

			}


	}