Black Screen after booting CentOS 7 on VirtualBox

Question

We have experienced a "black screen of death" after booting a CentOS virtual machine running on an Oracle VirtualBox. The screen is completely black, there is no mouse pointer. This seems to be related to upgrading the system, but we are not sure.

We've discovered that reinstalling guest additions and rebooting somehow fixes the problem. Here are the steps used to recover:

1. boot the VM, the screen should be black.
2. Ctrl + F2 -> a console login screen should be visible
3. On virtual box menu, [Devices] -> Insert Guest Additions CD Image...
4. Login to your linux system
5. su (or use sudo whenever required)
6. mkdir /media/cdrom
7. mount /dev/sr0 /media/cdrom
8. cd /media/cdrom
9. sh VBoxLinuxAdditions.run uninstall
10. sh VBoxLinuxAdditions.run install
11. reboot

Since we now know how to recover from the black screen, this is not a big problem. Still, anyone knows why this happens and how to avoid it?

Answer 1

Anytime you upgrade the kernel, you need to rebuild all kernel modules.

VirtualBox Guest Additions are implemented as a kernel module so it would need to be rebuilt/updated anytime the kernel is.

As for why your virtual machine does not boot without functioning Guest Additions, you are most likely using some feature during boot that is only provided by Guest Additions. If your CentOS is running a desktop, it is possible that only the display is nonfunctional and you may still be able to connect via other means (i.e. SSH if available).

Answer 2

I have hit this issue recently. In my case it was happening because it requires the password change and it requires the new password to be set before the UI loads. As a workaround we can reset the password. To do that we can follow the below steps

1. once the black screen appears click on ctrl+alt+f2
2. Asks for a login, Provide existing password
3. Now it asks for password change. Provide current password and new password of your choice
4. Restart the VM