Login as root and run ip address list to discover the IP address that the server got. In my case it is 192.168.56.101

Download Putty. Insert IP address and click on Open button

Login with an username and password.

First perform these steps – Installing Linux on Oracle Virtualbox – Basic Setup

Insert the media for CentOS 6 then start the virtual machine

Choose Install or upgrade an existing system

Skip media test

Click Next

Choose a language

Choose your keyboard

Choose basic storage. The other option is to use SAN LUN devices

Yes, discard any data

Set a hostname and then click Configure Network

Edit both network interfaces

Click on Connect Automatically

Choose nearest city to calculate the time

Set root password

Replace existing system

Write changes to disk

Install a minimal server. You can install additional software later

Then reboot

Continue to Installing Linux on Oracle Virtualbox – Connecting with Putty terminal emulator

Create a new virtual machine. I’m calling mine CentOS 6 Base

Set how much memory you would like. I’m setting mine with 1GB of RAM

Creating a new hard drive

Choose VDI (VirtualBox Disk Image)

Dynamically allocated

CentOS 6 Base is the name and I set to 20GB

Checking Virtual Machine Properties. Network section, Adapter 1 set to NAT

Adapter 2 set to Host-only adapter

If you are behind a corporate proxy, go to File, Preferences, and set Proxy to your proxy and port

Continue to Installing Linux on Oracle Virtualbox – CentOS 6