Symfony 3.1 Ldap身份验证不起作用

我正在使用Symfony 3.1开发一个应用程序，在Ldap身份验证方面遇到问题。以下代码：

services.yml

ldap:
    class: 'Symfony'Component'Ldap'LdapClient'
    arguments:
        - server.test.br   # host
        - 389         # port
        - 3           # version
        - false       # SSL
        - false        # TLS

security.yml

security:
providers:
    chain_provider:
        chain:
            providers: [my_ldap]
    my_ldap:
        ldap:
            service: ldap
            base_dn: dc=test,dc=br
            search_dn: cn=s00027,ou=Contas Administrativas de Sistemas,ou=Departamento de Tecnologia,dc=test,dc=br
            search_password: pass
            default_roles: ROLE_USER
            uid_key: sAMAccountName
            filter:  '({uid_key}={username})'
firewalls:
    dev:
        pattern: ^/(_(profiler|wdt)|css|images|js)/
        security: false
    admin:
        anonymous: true
        pattern:   ^/
        form_login_ldap:
            provider: chain_provider
            service: ldap
            dn_string: 'sAMAccountName={username}'
            check_path: /login_check
            login_path: /login
        logout:
            path: /logout
            target: /
    default:
        form_login_ldap:
            provider: chain_provider
            service: ldap
            dn_string: "uid={username},DC=test,DC=br"
            check_path: /login_check
            login_path: /login
access_control:
    - { path: ^/login, roles: IS_AUTHENTICATED_ANONYMOUSLY }
    - { path: ^/admin, roles: ROLE_ADMIN }

SecurityController.php

 /**
 * @Route("/login_check", name="login_check")
 */
public function loginAction(Request $request) {
    $authenticationUtils = $this->get('security.authentication_utils');
    $error = $authenticationUtils->getLastAuthenticationError();
    $lastUsername = $authenticationUtils->getLastUsername();
    return $this->render(
                    'AppBundle:Security:login.html.twig', array(
                // last username entered by the user
                'last_username' => $lastUsername,
                'error' => $error,
                    )
    );
}

我已经尝试了我所能尝试的一切，在日志中没有收到任何错误，只有关于LdapClient类的消息被弃用。

有人能帮我吗？请