SQLSTATE[HY000] [2002] Can't connect to local MySQL server through socket '/var/lib/mysql/mysql.sock' (2)

#0 /var/www/vhosts/gazelle/magento/lib/Zend/Db/Adapter/Pdo/Mysql.php(109): Zend_Db_Adapter_Pdo_Abstract->_connect()
#1 /var/www/vhosts/gazelle/magento/lib/Varien/Db/Adapter/Pdo/Mysql.php(320): Zend_Db_Adapter_Pdo_Mysql->_connect()
#2 /var/www/vhosts/gazelle/magento/lib/Zend/Db/Adapter/Abstract.php(460): Varien_Db_Adapter_Pdo_Mysql->_connect()
#3 /var/www/vhosts/gazelle/magento/lib/Zend/Db/Adapter/Pdo/Abstract.php(238): Zend_Db_Adapter_Abstract->query('SET NAMES utf8', Array)
#4 /var/www/vhosts/gazelle/magento/lib/Varien/Db/Adapter/Pdo/Mysql.php(428): Zend_Db_Adapter_Pdo_Abstract->query('SET NAMES utf8', Array)
#5 /var/www/vhosts/gazelle/magento/app/code/core/Mage/Core/Model/Resource.php(169): Varien_Db_Adapter_Pdo_Mysql->query('SET NAMES utf8')
#6 /var/www/vhosts/gazelle/magento/app/code/core/Mage/Core/Model/Resource.php(110): Mage_Core_Model_Resource->_newConnection('pdo_mysql', Object(Mage_Core_Model_Config_Element))
#7 /var/www/vhosts/gazelle/magento/app/code/core/Mage/Core/Model/Resource/Db/Abstract.php(320): Mage_Core_Model_Resource->getConnection('core_write')
#8 /var/www/vhosts/gazelle/magento/app/code/core/Mage/Core/Model/Resource/Db/Abstract.php(350): Mage_Core_Model_Resource_Db_Abstract->_getConnection('write')
#9 /var/www/vhosts/gazelle/magento/app/code/core/Mage/Core/Model/Resource/Db/Abstract.php(335): Mage_Core_Model_Resource_Db_Abstract->_getWriteAdapter()
#10 /var/www/vhosts/gazelle/magento/app/code/core/Mage/Core/Model/Resource/Cache.php(53): Mage_Core_Model_Resource_Db_Abstract->_getReadAdapter()
#11 /var/www/vhosts/gazelle/magento/app/code/core/Mage/Core/Model/Cache.php(478): Mage_Core_Model_Resource_Cache->getAllOptions()
#12 /var/www/vhosts/gazelle/magento/app/code/core/Mage/Core/Model/Cache.php(520): Mage_Core_Model_Cache->_initOptions()
#13 /var/www/vhosts/gazelle/magento/app/code/core/Mage/Core/Model/App.php(1183): Mage_Core_Model_Cache->canUse('config')
#14 /var/www/vhosts/gazelle/magento/app/code/core/Mage/Core/Model/Config.php(414): Mage_Core_Model_App->useCache('config')
#15 /var/www/vhosts/gazelle/magento/app/code/core/Mage/Core/Model/Config.php(294): Mage_Core_Model_Config->_canUseCacheForInit()
#16 /var/www/vhosts/gazelle/magento/app/code/core/Mage/Core/Model/App.php(413): Mage_Core_Model_Config->loadModulesCache()
#17 /var/www/vhosts/gazelle/magento/app/code/core/Mage/Core/Model/App.php(343): Mage_Core_Model_App->_initModules()
#18 /var/www/vhosts/gazelle/magento/app/Mage.php(684): Mage_Core_Model_App->run(Array)
#19 /var/www/vhosts/gazelle/magento/index.php(108): Mage::run('default', 'store')
#20 {main}