I'm a bit at a loss. I'm running a MySQL database that's roughly 1GB data in indices combined on a dedicated Linux server. DB version is '5.0.89-community'. Configuration is controlled via cPanel.

PHP actually runs elsewhere on a shared hosting. IP addresses are static and don't change. Access from remote IP address is properly configured. Website gets around 10K hits per day with each hit generating a a database query. Some of these queries are expensive (~1 sec execution time).

All is fine and well until at some point DB server starts refusing connections from the client, claiming that specific user can't access the server from that IP. Resetting the server will always fix the problem for a day or two and then the same thing happens.

There are some other DBs on that server, some of which are hit pretty hard on occasion but constantnly. One of the apps maintains several persistent connections since it does couple of updates per minute. Though I don't think it's related.

What's driving me mad is that I can't figure out why server would start refusing connections. There is nothing in the logs. This server is a hosted dedicated server so hosting company created the OS image and I didn't write or go over every line of configuration. I'd do it but I'm at a loss as to where start looking.

Any advice is appreciated.