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

#0 /var/www/html/trinity/common/propel/runtime/lib/Propel.php(574): Propel::initConnection(Array, 'zyndio')
#1 /var/www/html/trinity/common/propel/runtime/lib/Propel.php(600): Propel::getMasterConnection('zyndio')
#2 /var/www/html/trinity/common/propel/runtime/lib/Propel.php(550): Propel::getSlaveConnection('zyndio')
#3 /var/www/html/trinity/common/propel/runtime/lib/query/ModelCriteria.php(1217): Propel::getConnection('zyndio', 'read')
#4 /var/www/html/trinity/common/propel/runtime/lib/query/ModelCriteria.php(1123): ModelCriteria->getSelectStatement(NULL)
#5 /var/www/html/trinity/models/searchcategorydata.class.php(101): ModelCriteria->findOne()
#6 /var/www/html/trinity/controllers/pages/catpagecontroller.class.php(37): SearchCategoryData->getCategoryByDomainKey('Residential-Tre...')
#7 /var/www/html/trinity/controllers/pages/yunkpagecontroller.class.php(127): CatPageController->makePage()
#8 /var/www/html/trinity/controllers/core/core.class.php(379): YunkPageController->run()
#9 /var/www/html/trinity/controllers/core/core.class.php(548): Yunk::pageController()
#10 /var/www/html/trinity/html/zyndio.php(7): Yunk::run('page')
#11 {main}