Jeff Wilson 
A VPS or a virtual private server provides a complete resource isolation, meaning the hardware resources like CPU, hard disk space and memory assigned to a specific virtual server are dedicated and fully available to it at all times. In a shared hosting environment all accounts on the physical server share the resources of the host server and many resources are capped and limited in order to save the host server from unexpected overuse.
The objective of this guide is to enable Sendmail’s virtual user table, which allows us to configure user-specific and domain-wide email aliases for multiple domains. These instructions assume you are using a CentOS virtual server.
Linux VPS hosting has become very popular among businesses, programmers and developers nowadays, mainly due to its many advantages in terms of cost effectiveness, flexibility, better performance, security, stability, reliability and functionality of course. As an operating system GNU/Linux became the world’s most dominant hosting solution for Internet hosting businesses mainly because of the many benefits you’ll get by using it on your servers.
So, why is a Linux based VPS better choice than a Windows based VPS?
Mark Shuttleworth, Ubuntu’s founder has announced the codename for the upcoming Ubuntu release: Ubuntu 12.10 will be called Quantal …