It is very easy to accept a Linux OS update on either Ubuntu or CentOS. We install server-version Operating Systems on Desktops and Servers, and should not be updated if they are already working with display. Server Linux systems SHOULD NOT be treated like Windows system, as you or whoever manages these systems at your site should create back-ups/images manually before making changes. There are a lot of components involved with the Linux Operating base-system, connected drives, and other hardware devices that rely on the stability of the Linux OS. Updating without knowledge of knowing what the updates are for will usually cause usability issues. A common issue reported is that the display driver breaks, and now you no longer have display (or a login screen when you reboot your system).

If you have a server, we usually recommend NOT to update, or run any update commands ('yum' or 'apt-get' update/upgrade commands). If this is a server or an integral part of your team/work/lab workflow that works as-is, and that you DO NOT want to take chances on any changes made to the system, then it probably is not a good idea to update it.

If you have the desktop version (usually installed on your own on a home-PC), then update at your own discretion.

If you are unsure on what the update will change and do for your system/team, then you should speak to your local Linux IT/Administrator (network IT/security) onsite to determine if updating the Linux OS is necessary. Most cases, Linux updates are not necessary if you have a system that is already working for everyone else.

Why does updating my Linux OS 'break' my NVIDIA driver?

GPU driver is compiled against the specific kernel. Earlier NVIDIA driver installations required us to point the installation file to the specific list of installed kernels. We used to look up the current kernel-header version that we were logged into, and then point the NVIDIA driver run file to run against it. 

sh NVIDIA-Linux-x86-1.0-7182-pkg1.run --kernel-name='KERNEL_NAME'

If you updated your kernel, then the NVIDIA driver is linking to the old one that got overwritten. So technically 'broken' since it doesn't work for your updated kernel.

I updated my Linux OS, and now I have no display. Why?

Your Linux OS updated and set a new kernel-header, and the NVIDIA driver you had installed is pointed to the old one.

How do I fix my NVIDIA driver if it is not functioning after a Linux OS update?

Get to a terminal, and re-install the NVIDIA driver. If you know what Graphics Card you have, then go ahead and search for the drivers from here:

https://www.nvidia.com/Download/index.aspx?lang=en-us

I'm working on updating these, but these articles might help you obtain the latest NVIDIA driver and run the install file through the command lines.

Reinstall NVIDIA drivers for CentOS 7.x

Reinstall NVIDIA drivers for Ubuntu 16.04 (if you have Ubuntu 18.04/20.04, the command to run right before running the file is 'init 3')