Fatal error: Uncaught exception Exception with message Too many connections thrown in system/modules/core/library/Contao/Database/Mysql.php on line 69

#0 system/modules/core/library/Contao/Database.php(77): Contao\Database\Mysql->connect()
#1 system/modules/core/library/Contao/Database.php(160): Contao\Database->__construct(Array)
#2 [internal function]: Contao\Database::getInstance()
#3 system/modules/core/library/Contao/System.php(110): call_user_func(Array)
#4 system/modules/core/library/Contao/User.php(89): Contao\System->import('Database')
#5 system/modules/core/classes/FrontendUser.php(79): Contao\User->__construct()
#6 system/modules/core/library/Contao/User.php(151): Contao\FrontendUser->__construct()
#7 [internal function]: Contao\User::getInstance()
#8 system/modules/core/library/Contao/System.php(110): call_user_func(Array)
#9 index.php(41): Contao\System->import('FrontendUser', 'User')
#10 index.php(414): Index->__construct()
#11 {main}

Warning: Unknown: write failed: No space left on device (28) in Unknown on line 0

#0 [internal function]: __error(2, 'Unknown: write ...', 'Unknown', 0, NULL)
#1 {main}

Warning: Unknown: Failed to write session data (files). Please verify that the current setting of session.save_path is correct (/var/lib/php/session) in Unknown on line 0

#0 [internal function]: __error(2, 'Unknown: Failed...', 'Unknown', 0, NULL)
#1 {main}