Fatal error: Connecting to MySQL server 'localhost' failed.

You get more information about the problem in our knowledge base: http://www.woltlab.com/help/?code=1040

Information:

error message: Connecting to MySQL server 'localhost' failed.
error code: 1040
sql type: MySQLDatabase
sql error: Too many connections
sql error number: 1040
sql version:
file: /var/www/web6/html/wcf/lib/system/database/MySQLDatabase.class.php (29)
php version: 5.2.17-0.dotdeb.0
wcf version: 1.0.11 pl 4 (Horizon)
date: Fri, 26 May 2017 07:12:12 +0000
request: /index.php?page=Register&s=8c58db727f8b6d80cdbcfd224aff82b64c6a99f3
referer:

Stacktrace:

#0 /var/www/web6/html/wcf/lib/system/database/Database.class.php(76): MySQLDatabase->connect()
#1 /var/www/web6/html/wcf/lib/system/WCF.class.php(270): Database->__construct(...)
#2 /var/www/web6/html/wcf/lib/system/WCF.class.php(88): WCF->initDB()
#3 /var/www/web6/html/global.php(18): WCF->__construct()
#4 /var/www/web6/html/index.php(7): require_once('/var/www/web6/h...')
#5 {main}