If you’ve ever tried to create a multiboot/multiOS system then you most likely became disenchanted with grubs boot-strap. With some experimenting I’ve learned to write my own grub2 custom linux boot menus (scripts). I’ve also found better tools that allow me to save and restore grub when things go wrong. Here are 2 of the top-10 (PPA) config repositories I run when installing a new DebianOS using grub2.
sudo add-apt-repository ppa:danielritchter2007 grub-customizer
sudo add-apt-repository ppa:yannubuntu/boot-repair (**dead in Fossa Ubuntu20)
To make these grub tools work you must then run system-update not (grub-update), and install from the command line.
sudo apt-get update
sudo apt-get install boot-repair
sudo apt-get grub-customizer
The first thing I do is run a grub-snapshot using boot-repair. Its the second command in the GUI menu. It should ask you where you want to keep a copy of the boot-repair log if all goes well. A note here is the pastebin linker is broken for Fossa.
Grub-customizer will give you a GUI menu for diddling with and changing your boot menu. It’s very useful for understand how multiboot systems work. However it doesn’t handle boot-icons or splash-screens very well. You might have to tweak those manually. It will give you access to all of GRUB2 extended menu options and flash boot-flags.
This articles tag line is superGrub and you can google super-grub to find an install package for it. However, I found that HybirdX4 (superGrub) to be of more use when dealing with firmware issues on Acer PCs. The GRUB extension commands using CMS-grub enter >>vmfirm or --help from grub command line. Your systems firmware settings menu should pop open. This little trick is very useful for Acer’s with a stuck F2 button. It’s a bit safer too than opening up the case to remove the cmos battery. Otherwise, to get to the grub command line you will have to boot in “recovery-mode” then enter --help. If your running plain grub then a short menu appears. If your using super-grup then an extended menu appears of which vmfirm is included.
One limitation of grub-customizer is it won’t allow you to down-grade microcode-firmware releases or backup firmware. For example want to downgrade the rolling firmware update from microcode ver3.20180524.1 to ver2-20160316-1-3 for AMDx64 then I have to build a custom kernel for that. There isn’t a tool that I’m aware of that does that. If I want to back up my systems firmware then I have to use DOS tool called AUFDOS/AUFWIN to backup and wipe CMOS. Also these tools are limited to x32-arch so the uper x64 bits are never actually wiped. I’ve used tools from www-dot-allbootdisk-dot-com to fix flash-boot issues but none fo them actually fix firmware-update issues.
Hopefully we will have better firmware source control in the future however for now your taking changes by applying Debian-firmware updates. An example of this is when my flash drive geometry was changed by a rolling update. I first thought the flash drive was dead only to discover some months later by using a windows tool called Malvastyle_USB_fixer that the disks geometry had been corrupted. To think I nearly threw it away! Since that time I never boot a new Linux_OS without using the expert mode key >>“e --dis-ucode-ldr” to turnoff firmware payloads that might damage my drives or render my system inoperative. If your aware of better firmware tools please enter them here?