I'm using Virtual Box on my windows 8.1 host machine. I have installed CentOS & Ubuntu in 'Graphical Mode' and had sufficient practice. But now I wanted to switch to 'Command Line Mode" completely. Therefore created a machine for that purpose and installed 'CentOS6.6 Basic Server'/'CentOS7 Minimal.
On Graphical Mahines, I could easily install VBox Guest Additions with these few commands.
yum update yum install gcc yum install kernel-devel sh VBoxLinuxAdditions.run (From mounted Location For CDrom)
But since I installed CLI machine and when tried same commands on it, it does not install properly, gives this error:
Could not find X.Org or Xfree86 Window System, skipping.