Install CentOS 7 Into VirtualBox

1. Create VM

• 16GB Dynamic Drive
• 2 vCPU
• 2GB RAM
• PAE
• 128MB Video
• 3D Acceleration

2. Install OS

• Attach DVD Image
• Start VM
• Right-Ctrl is the default host key (to free mouse and keyboard)
• Test Media (Optional) or Install
• Choose Language 
• Software Selection - Development and Creative Workstation
• Installation Destination - Select disk and automatic partitioning
• Network and Hostname - Enable and configure required NIC and Hostname
• Begin Installation
• Set root password
• Create your non-root user (make user administrator)
• Wait :)
• Reboot
• Accept license
• Finish configuration
• Configure Kdump
• Logon

3a. Patch (GUI)

• You only need to do 3a. or 3b. not both as for all the following (a) and (b) sections.
• Need to update before compiling Guest Additions else newly downloaded software will not match existing versions
• Applications > System Tools > Software Update
• Install Updates
• Reboot

3b. Patch (CLI)

• sudo yum update
• Reboot

Sections 4 and 5 are optional - There are no RHEL\CentOS7 DKMS modules available yet, but I have left these sections in for reference.

4a. Add RPMForge repo (GUI)

• Download latest RPMforge release from http://pkgs.repoforge.org/rpmforge-release
• As of writing for x86 this is http://pkgs.repoforge.org/rpmforge-release/rpmforge-release-0.5.3-1.el7.rf.x86_64.rpm
• Open using Package Installer 
• Install when offered

4b. Add RPMForge repo (CLI)

• Download repo RPM using wget http://pkgs.repoforge.org/rpmforge-release/rpmforge-release-0.5.3-1.el7.rf.x86_64.rpm
• install rpm -i rpmforge-release-0.5.3-1.el6.rf.x86_64.rpm

5. Install DKMS

• sudo yum install dkms

6. Install development tools

• sudo yum groupinstall “Development Tools”
• sudo yum install kernel-devel

7. Install Guest Additions

• There appears to be a bug with building the additions from the addition CD
• Details here: https://www.virtualbox.org/ticket/12638
• Matthew Casperson has kindly made a patched version in his blog 
• Download
• Extract using bunzip2
• Extract using tar
• Install using sudo ./install.sh