Prerequisites:
- VirtualBox
- Installed CentOS7 in VirtualBox
Step 1:
Start your CentOS7
Step 2:
Open Terminal. (make sure your CentOS is connected to the internet)
![](https://www.nucleiotechnologies.com/wp-content/uploads/2022/02/terminal2.png)
Step 3:
Enter the following commands:
sudo yum install gcc
![](https://www.nucleiotechnologies.com/wp-content/uploads/2022/02/installation-confirmation-1024x747.png)
Type “y” when the asks requires your confirmation.
Sudo yum install kernel-devel-$(uname –r)
Again, type “y” when the process asks for your confirmation.
Step 4:
Close the terminal and click the “Device” on the upper left and then click “Insert Guest Additions CD image…”
![](https://www.nucleiotechnologies.com/wp-content/uploads/2022/02/guest-addition-1024x744.png)
Step 5:
Click “run”. It will require you to enter your user password.
![](https://www.nucleiotechnologies.com/wp-content/uploads/2022/02/run-1024x745.png)
![](https://www.nucleiotechnologies.com/wp-content/uploads/2022/02/password-1024x746.png)
Step 6:
It will run a program in terminal. When it is done, press Enter.
![](https://www.nucleiotechnologies.com/wp-content/uploads/2022/02/press-return-1024x744.png)
Step 7:
Reboot your CentOS.
![](https://www.nucleiotechnologies.com/wp-content/uploads/2022/02/reboot-1024x744.png)
Step 8:
After successfully rebooting, go to “view” and click “full screen mode”.
![](https://www.nucleiotechnologies.com/wp-content/uploads/2022/02/click_fullscreen.png)
![](https://www.nucleiotechnologies.com/wp-content/uploads/2022/02/fullscreen-1024x576.png)
NOTE:
If you want to exit full screen mode, hover your mouse at the bottom center, it will show the options.