Trying to install modules gives an error

Hi There,

I have tried to install a module, but in the terminal it generates the following error:
Started in the root (where fuel and index.php are located)

php index.php fuel/installer/install validate

A PHP Error was encountered

Severity: Warning
Message: mysqli::real_connect(): (HY000/2002): No such file or directory
Filename: /Applications/MAMP/htdocs/newsent/fuel/codeigniter/database/drivers/mysqli/mysqli_driver.php
Line Number: 201

Backtrace:
File: /Applications/MAMP/htdocs/newsent/fuel/modules/fuel/core/Loader.php
Line: 473
Function: DB

File: /Applications/MAMP/htdocs/newsent/fuel/modules/fuel/core/MY_Model.php
Line: 159
Function: database

File: /Applications/MAMP/htdocs/newsent/fuel/modules/fuel/core/MY_Model.php
Line: 112
Function: initialize

File: /Applications/MAMP/htdocs/newsent/fuel/modules/fuel/core/Loader.php
Line: 241
Function: load_class

File: /Applications/MAMP/htdocs/newsent/fuel/modules/fuel/core/Loader.php
Line: 455
Function: model

File: /Applications/MAMP/htdocs/newsent/fuel/modules/fuel/libraries/Fuel_modules.php
Line: 969
Function: module_model

File: /Applications/MAMP/htdocs/newsent/fuel/modules/fuel/libraries/Fuel_permissions.php
Line: 71
Function: model

File: /Applications/MAMP/htdocs/newsent/fuel/modules/fuel/libraries/Fuel_permissions.php
Line: 52
Function: initialize

File: /Applications/MAMP/htdocs/newsent/fuel/modules/fuel/core/Loader.php
Line: 205
Function: __construct

File: /Applications/MAMP/htdocs/newsent/fuel/modules/fuel/core/Loader.php
Line: 448
Function: library

File: /Applications/MAMP/htdocs/newsent/fuel/modules/fuel/libraries/Fuel_advanced_module.php
Line: 1152
Function: module_library

File: /Applications/MAMP/htdocs/newsent/fuel/modules/fuel/libraries/Fuel_advanced_module.php
Line: 393
Function: load_library

File: /Applications/MAMP/htdocs/newsent/fuel/modules/fuel/libraries/Fuel.php
Line: 479
Function: attach

File: /Applications/MAMP/htdocs/newsent/fuel/modules/fuel/libraries/Fuel_installer.php
Line: 368
Function: __get

File: /Applications/MAMP/htdocs/newsent/fuel/modules/fuel/libraries/Fuel_installer.php
Line: 134
Function: create_permissions

File: /Applications/MAMP/htdocs/newsent/fuel/modules/fuel/libraries/Fuel_advanced_module.php
Line: 1238
Function: install

File: /Applications/MAMP/htdocs/newsent/fuel/modules/fuel/controllers/Installer.php
Line: 62
Function: install

File: /Applications/MAMP/htdocs/newsent/index.php
Line: 364
Function: require_once

Database error: A Database Error Occurred

Unable to connect to your database server using the provided settings.
Filename: /Applications/MAMP/htdocs/newsent/fuel/modules/fuel/core/MY_Model.php
Line Number: 112

I have the database setup correctly, as I can see the dashboard of the fuelcms.

So what is wrong?