1. Ready the Guest ISO
2. Mount the iso
mkdir /mnt/iso
mount -o loop redhat.iso /mnt/iso
3. Setup up yum to local ISO
https://access.redhat.com/solutions/1355683
4. Set Optical drive to Guest Addtitions
Menu-> Device -> Insert Guest Additions CD Image
5. mount the cdrom
mkdir -p /media/cdrom
mount /dev/sr0 /mnt/cdrom
6. try to install VBox Guest (requires gcc, kernel header)
cd /mnt/cdrom/
./VBoxLinuxAdditions.run
6a. Install any packages that is required when the installation failed
yum install bzip2
yum install gcc
yum install perl
yum install kernel-devel
yum install gcc
yum install perl
yum install kernel-devel
./VBoxLinuxAdditions.run
7. In the menu, setup the sharing folder
8. Adding group vboxsf to root or any other users
usermod -G vboxsf root
9. Auto-mount
reboot guest
ls /media/sf_(sharename)
10. Manual mount the shared folder
mkdir -p /shared/sharename
mount -t vboxsf sharename /shared/sharename
11. Adding to /etc/fstab
sharename /shared/sharename vboxsf defaults 0 0
12. Adding to /etc/modules
vboxsf
13. Mount sharename
mount sharename