SQL-DATABASE ERROR

Database error in WoltLab Burning Board (): Link-ID == false, connect failed
mysql error: Unknown MySQL server host 'db05.puretec.de' (0)
mysql error number: 2005
mysql version: unknown
php version: 5.2.17
Date: 20.01.2017 @ 23:10
Script: /wbb2/portal.php
Referer: