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

You get more information about the problem in our knowledge base: http://www.woltlab.com/help/?code=2003

Information:

error message: Link-ID == false, connect failed
error code: 2003
sql type: MySQLDatabase
sql error: Can't connect to MySQL server on '10.8.11.90' (4)
sql error number: 2003
sql version:
file: /home/content/42/11868642/html/outlanta/forum/wcf/lib/system/database/MySQLDatabase.class.php (29)
php version: 5.2.17
wcf version: 1.0.0
date: Tue, 22 Oct 2019 14:32:30 +0000
request: /forum/wbb/index.php?page=User&userID=244326
referer:

Stacktrace:

#0 /home/content/42/11868642/html/outlanta/forum/wcf/lib/system/database/Database.class.php(72): MySQLDatabase->connect()
#1 /home/content/42/11868642/html/outlanta/forum/wcf/lib/system/WCF.class.php(206): Database->__construct(...)
#2 /home/content/42/11868642/html/outlanta/forum/wcf/lib/system/WCF.class.php(46): WCF->initDB()
#3 /home/content/42/11868642/html/outlanta/forum/wbb/global.php(15): WCF->__construct()
#4 /home/content/42/11868642/html/outlanta/forum/wbb/index.php(7): require_once('/home/content/4...')
#5 {main}