SQL-DATABASE ERROR

Database error in WoltLab Burning Board (): Link-ID == false, connect failed
mysql error: Too many connections
mysql error number: 1040
mysql version: unknown
php version: 5.6.11-1~dotdeb+7.1
Date: 24.06.2017 @ 22:43
Script: /board.php?boardid=1&sid=0be4c5c7413843a5d32679d039fc0d1c
Referer: