it is pretty cool… a 32Bit Linux Host can run a 64Bit Linux guest. NICE 😉

i assume you have a working CentOS7 basic installation and are root.

tested on/with:

tested with: Host: Debian 8 Jessie and CentOS7

Operating System: Debian GNU/Linux 8 (jessie) + VirtualBox 5.2.2
Kernel: Linux 3.16.0-4-686-pae
Architecture: x86

Operating System: CentOS Linux 7 (Core) + VirtualBox 5.2.6
Kernel: Linux 3.10.0-693.17.1.el7.x86_64
Architecture: x86-64

Guest: CentOS7

   Static hostname: localhost.localdomain
    Virtualization: kvm
  Operating System: CentOS Linux 7 (Core)
       CPE OS Name: cpe:/o:centos:centos:7
            Kernel: Linux 3.10.0-693.11.1.el7.x86_64
      Architecture: x86-64

now let’s go:

yum update && yum upgrade; # first you will have to get CentOS7 up to date
yum install htop; # i just love this tool
yum install epel-release; # whatever this does
# OPTIONAL: if you want a gui
yum groupinstall "X Window system"; # this installs the basic grafical system <-
yum groupinstall "MATE Desktop"; # this installs mate
systemctl isolate; # this makes linux boot the grafical profile per default
unlink /etc/systemd/system/
ln -s /usr/lib/systemd/system/ /etc/systemd/system/

reboot; # you might reboot now or not

now i hope you have mate up and running and want to install those cool integration tools: let’s install the virtualbox additions:

you will have to insert the virtual cd into the virtual cdrom drive like this:

this should do the job:

mkdir /virtualbox; # i copy the files from cdrom to harddisk /virtualbox... just got used to this workflow.
mount; # checkout where cdrom was mounted
lsblk -fs
sda1 xfs boot a67115fc-1ad2-4fba-9147-7e9af3d6f816 /boot
sda2 xfs home f75b9798-6193-4335-bd34-22f2d6c62f69 /home
sda3 xfs root 5b020a17-bb15-4507-81b9-b9b30d0e83de /
sda5 swap 0cbab842-7f2d-4655-8fa5-028d03120a9f [SWAP]
sr0 iso9660 VBox_GAs_5.2.6 2018-01-15-13-59-52-30 
# if not mounted automatically mount it manually
mkdir -p /run/media/cdrom; # make mount point
mount /dev/sr0 /run/media/cdrom/; # mount cdrom.iso
cd /run/media/user/VBox_GAs_5.2.2/; # in the debian8 case cdrom.iso was mounted here
cd /run/media/cdrom/; # in the CentOS7 case, it is not mounted automatically

cp -rv * /virtualbox/
cd /virtualbox/

yum install kernel-devel; # what you will need to compile the guest additions module
yum install gcc make perl bzip2

reboot; # reboot system to load kernel modules

proof that it is working


while you are on it

speed up boot

yum install epel-release;
yum update;
yum install vim net-tools htop; # install basic tools
vim /etc/default/grub # modify 1 = wait 1 second until entry 0 is booted GRUB_DEFAULT=0 GRUB_TIMEOUT=1 # centos7 grub2-mkconfig grub2-mkconfig -o /boot/grub2/grub.cfg