Thanks for this! For me, it was actually turning secure boot off. I know this is an older thread, but I want to note this somewhere on the interwebs in case somebody else needs it. So I am running my VMWare ESXi Host at version 8 and CentOS 9. I had my hardware set for 8 too. For some reason, my Ubuntu install "disk" worked fine, but my CentOS9 DVD ISO wouldn't boot. I turned off Secure Boot and it booted up fine.