Originally Posted by razordave
Usually this is caused by 'too many connections' to the database server. You can try to log in via the command prompt and then issuing the command: show processlist;
This will show the current connections to the server. If it can't connect, it should give you an error.
To fix, either reduce the amount of connections to the SQL server (using caching or something similar) or increase the number of connections MySQL is allowed to have (using max_connections in my.cnf)
Hope that points you in the right direction.
Thanks to you i realized that i had totally forgotten to use a caching plugin for a few of these websites.
The issue is still there and my host is still unable to find a reason of this. I have already told my host what RoseHosting
have suggested and i hope this'll help us (me & my host) to get to the solution.