1. Setup Hostname
This hostname cannot be the same as any domain that is on your server (for example, if example.com is a domain on your server, use hostname.example.com as your fully qualified hostname).
You can use the following command for hostname setup eg. srv1.example.com
hostname srv1.example.com
2. Setup Server IP addresses
Define additional IP address, subnet address, and default gateway IP address for your server — your service provider can provide you with this information.
3. Software Requirements
You must have a clean/fresh installation of supported operating systems:
CentOS 6, RedHat 6 or CloudLinux 6, MINIMAL installation and English version only!
CentOS 7 is also supported, we recommend minimal version.
4. Hardware Requirements
(not recommended) 32 bit operating systems require a minimum of 512 MB RAM
64 bit operating systems require a minimum of 1024 MB RAM (recommended)
Recommended System: 4 GB+ RAM so you would have the full functionality such as Anti-virus scan of emails.
OPTIONAL: You can download CentOS 6/7 Installation here (if your hosting provider doesn’t offer it)
Download CentOS 6.x – 32bit (minimal)
http://isoredirect.centos.org/centos/6/isos/i386/
Download CentOS 6.x – 64bit (minimal) (recommended)
http://isoredirect.centos.org/centos/6/isos/x86_64/
Download CentOS 7.x – 64bit (minimal) (recommended)
http://isoredirect.centos.org/centos/7/isos/x86_64/
Download CentOS for openVZ
http://wiki.openvz.org/Download/template/precreated