I had a server stuck on
"Welcome To Grub" screen running Debian 12. (did not even go to GRUB prompt)
This was after doing apt-update / upgrade a couple days ago.
This machine was just installed and configured a little over a month ago.
It's a supermicro server. IPMI is not accessible using modern java, you have to go get an old version from oracle site (jdk-8u431-linux-x64.tar.gz) unpack it and run javaws in jdk1.8.0_431/jre/bin (ie ./javaws ~/Downloads/launch.jnlp) (launch.jnlp is the file you get by clicking on the 'preview' image in the web IPMI console)
that javaws app will let you mount a local iso (like debian iso) using Virtual Media menu option.. that works you just have to be patient while it uploads to the BMC
anyhow, i haven't figured it out yet but somehow apt upgrade messed up UEFI / Secure boot. SuperMicro has some key functions in bios settings (including something about getting a license from them) but i didn't mess with that.
The solution was to enable CMS mode in SuperMicro bios, which is "legacy mode". After I set that the machine booted fine without any issue... May not be the correct solution but it's running.
