A Virtual Private Server or VPS is a way to have many of the benefits of a dedicated server without actually having one. For the customer, it means having his/her own server while still working in a managed system environment, at a fraction of the full server cost. For the owner of the dedicated server it is a way to fully utilize a server that might otherwise be only partially used. Furthermore, you can offer customers the freedom of having their own servers without the security risk.
Some common virtualization solutions include Xen, VMware, Virtuozzo, and OpenVZ. Here are a few things to consider when preparing your dedicated server for virtualization:
1. Determine how much RAM and CPU power you can afford to distribute among each VPS. Remember, each one will essentially be running an entire operating system. Make sure your server box is really designed to be a server (i.e. multiple cores/processors and a ton of RAM).
2. Enable tight security features in whatever software you use. With a VPS, no user should be able to get out of their virtual machine,and they certainly should not be able to gain root access to the entire server.
3. If certain services are not going to be used on the main server, disable them. That will reduce server load and free up more RAM.
4. Don’t max out the server. It is tempting squeeze in as many VPS users as you can, but you need to leave a little overhead in case one or two are more taxing to the server than the others.
5. Considering number 4, you should make sure you have an idea about what types of sites are going to be hosted by the VPS and monitor their usage. If one VPS appears to be hyperactive, you might suggest that customer get a full dedicated server.