php magento setup:install --base-url="http://localhost/magento2"
--db-host="localhost" --db-name="magento2_db" --db-user="magento2_user"
--db-password="*password" --admin-user="admin"
--admin-password="*password" admin-firstname="admin"
--admin-lastname="user" --use-sample-data --cleanup-database

[RuntimeException]
Too many arguments.