Optimize Server Resources And Secure Server From Attack

I host about 20 websites on a Dedicated Virtual (dv) 3.5 server from [login to view URL] - I'm running Plesk 8.6.0 and CentOS 5 Lately I've been having some Quality of Service (QoS) issues where I'll average about 3 "black zones" per day, always at varying times during the day. I SHOULD have more than enough server resources to support all the websites I'm hosting with no problems. There is no reason for these black zones (or even yellow zones) to ever occur. I'm very familiar with this system, but unfortunately not a knowledgeable enough administrator to figure out what is causing these periodic mini-crashes and fix the issue. What I need is someone who can ssh into my system, study the logs, history and processes and figure out what the problems are, and report back to me. Then fix them. I've also been having a problem with foreign computers scanning my server for vulnerabilities. I'm assuming this is also sapping precious processor time and memory. If you could modify my Firewall in Plesk to automatically ban suspicious behavior like this that would be great. I would also like you to report on any other security holes or optimization opportunities you may see along the way. I've already followed much of MediaTemple's own guidelines for optimizing the server and making things run better. What I need here is someone with the knowledge to see what I've missed. ## Deliverables 1) All deliverables will be considered "work made for hire" under U.S. Copyright law. Employer will receive exclusive and complete copyrights to all work purchased. (No 3rd party components unless all copyright ramifications are explained AND AGREED TO by the employer on the site per the worker's Worker Legal Agreement). ## Platform CentOS 5 Plesk 8.6.0 MediaTemple