Getting back to working on a Linux VM on my home server; I had installed CentOS in a VM but apparently missed some things. My server rebooted due to some updates and I could no longer get the VM to boot. Fortunately … a combination of postings helped me out.
The first issue I had was that I kept booting off the virtual cd, and an attempt was being made at installing the OS again. I just removed the cd definition and I was then booting into a bios-like environment. This YouTube video helped me out there. The video is for ubuntu, but the key was that if you go to the “Boot Maintenance Manager”->”Boot From File”-> next prompt -> “EFI” -> “centos” -> “grubx64.efi” you will be booted into the installation of CentOS that you installed.
From this point, a tip specifically for CentOS was this post here. The key was to copy /boot/efi/EFI/centos/shimx64-centos.efi to /boot/efi/EFI/BOOT/BOOTX64.EFI. Apparently this can be done via a grub command line (another post indicates that “grub-install –efi-directory=/boot/efi –boot-directory=/boot –removable” would work, but I didn’t try it).
In any case, a manual copy of that file, and then reboot … and I’m back in business.
The only other issue I had doing what I’m trying to do required me to set sudo permissions so that my account isn’t prompted for a password. This post led me to the solution for that, in the post by Richipal.