Как корректно настроить Yii2 для работы на поддоменах?

$config = [
    'id' => 'basic',
    'basePath' => dirname(__DIR__),
    'bootstrap' => ['log'],
    'aliases' => [
        '@bower' => '@vendor/bower-asset',
        '@npm'   => '@vendor/npm-asset',
    ],
    'components' => [
        'request' => [
            // !!! insert a secret key in the following (if it is empty) - this is required by cookie validation
            'cookieValidationKey' => 'tratata',
            'baseUrl' => ''
        ],
        'cache' => [
            'class' => 'yii\caching\FileCache',
        ],
        'user' => [
            'identityClass' => 'app\models\User',
            'enableAutoLogin' => true,
        ],
        'errorHandler' => [
            'errorAction' => 'site/error',
        ],
        'mailer' => [
            'class' => 'yii\swiftmailer\Mailer',
            'useFileTransport' => true,
        ],
        'log' => [
            'traceLevel' => YII_DEBUG ? 3 : 0,
            'targets' => [
                [
                    'class' => 'yii\log\FileTarget',
                    'levels' => ['error', 'warning'],
                ],
            ],
        ],
        'db' => $db,
        'urlManager' => [
            'enablePrettyUrl' => true,
            'showScriptName' => false,
            'rules' => [
                '' => 'site/index',
                '<controller:\w+>/<action:\w+>/' => '<controller>/<action>',
            ],
        ],
    ],
    'params' => $params,
];

Options +FollowSymLinks
IndexIgnore */*
RewriteEngine On

RewriteCond %{REQUEST_URI} !^/(web)
RewriteRule ^assets/(.*)$ /web/assets/$1 [L]
RewriteRule ^css/(.*)$ web/css/$1 [L]
RewriteRule ^js/(.*)$ web/js/$1 [L]
RewriteRule ^images/(.*)$ web/images/$1 [L]
RewriteRule (.*) /web/$1

RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . /web/index.php