Fatal error: Link-ID == false, connect failed

You get more information about the problem in our knowledge base: http://www.woltlab.com/help/?code=2013

Information:

error message: Link-ID == false, connect failed
error code: 2013
sql type: MySQLDatabase
sql error: Lost connection to MySQL server at 'reading initial communication packet', system error: 0
sql error number: 2013
sql version:
file: /kunden/78331_22459/webseiten/forum3/wcf/lib/system/database/MySQLDatabase.class.php (29)
php version: 5.2.17
wcf version: 1.0.1 RC 1
date: Tue, 22 Sep 2020 07:53:05 +0000
request: /
referer:

Stacktrace:

#0 /kunden/78331_22459/webseiten/forum3/wcf/lib/system/database/Database.class.php(73): MySQLDatabase->connect()
#1 /kunden/78331_22459/webseiten/forum3/wcf/lib/system/WCF.class.php(216): Database->__construct(...)
#2 /kunden/78331_22459/webseiten/forum3/wcf/lib/system/WCF.class.php(46): WCF->initDB()
#3 /kunden/78331_22459/webseiten/forum3/global.php(15): WCF->__construct()
#4 /kunden/78331_22459/webseiten/forum3/index.php(7): require_once('/kunden/78331_2...')
#5 {main}