Problem

When you install RVsitebuilder 6 and Setup, it's error

Contact provider check install error log.

For Directadmin

tail -f /usr/local/rvglobalsoft/rvsitebuilder/var/install.log

For cPanel

tail -f /var/cpanel/rvglobalsoft/rvsitebuilder/var/install.log

Error

MDB2 Error: unknown error : _doConnect: [Error message: Too many connections]

Solution:
Please ask your host provider to edit file: /etc/my.cnf

[mysqld]
max_connections=500

And restart mysql with command:

service mysqld restart

ref.
https://docs.directadmin.com/other-hosting-services/mariadb-mysql/troubleshooting.html#mysql-connect-too-many-connections-unable-to-connect-to-sql-server