Warning: Too many connections!!

Guys recently we had a message displayed on the forum:
"The server is too busy, try later.."

anyway, we moved our forum into a private ded. server.
We set NIX* to zero becuas ethe server doesn't allow access to it.

but we noticed another problem, sometime we get the error message:

Warning: Too many connections in /home/httpd/vhosts/mydomain/httpdocs/forum/index.php on line 17

Warning: MySQL Connection Failed: Too many connections in /home/httpd/vhosts/mydomain/httpdocs/forum/index.php on line 17
Can't open connection to MySQL

What shall I do to avoid this problem?

[GrandAmGuru]

I had that problem too, make sure your Persistent Connections or "Simultaneous sessions limit" is set to 0

[Erwin]

That problem is unusual with a dedicated server. Increase the number of connections allowed in php.ini. Also, make sure you optimize your server - post in the "Server" forum on vB.com and ask advice from the server guru, eva2000. Turning persistent connection to "0" in your admin/config.php will help, but personally I keep it on as it increases the speed for the user slightly.

[HAK]

guys, the support at Vulletin adviced to increase the number of max_connections and I did from 100 to 200 but today until the moment, the site is freezed withe same problem.!!

I am afraid it is being hacked somehow gre: