[Aardwolf]

So from what I understand from these replies:

1. Windows will decide to undo your boot settings or grub every now and then? How can it do that, and can Linux do it too? If UEFI is "secure", is there no way to securely prevent windows from changing it?

2. UEFI does NOT support multiboot on multiple volumes? You cannot install different OSes on different disks? What if you put multiple SSD's and HDD's in a desktop computer, can you install a different OS on each and boot to any with UEFI? What about booting from USB sticks?

[josteink]

1. Any OS can update which UEFI boot-target is the default one (this is what parent poster complains about). It should however not interfere with another OSes config or files. Windows does not touch Grub (or the other way around). That messy, unsafe and unreliable approach is reserved for legacy BIOS boot.

2. UEFI supports clean and safe separation between boot-targets, across single volumes, multiple volumes and networks targets with cryptographic verification if desired (Secure boot). UEFI supports everything traditional BIOS boot supports and more. The same can not be said the other way around. It also boot straight into long-mode, meaning you don’t have to implement X86 mode-golf (and similar lessons in ancient history) at all in your OS-loader.

UEFI is rather overengineered, but it’s clearly a better approach with better support for modern use-cases built into the core design.

Think of UEFI as Grub built into your machine. With UEFI your individual OS’s bootloader should no longer need to handle/be aware of multi-booting. They should only boot themselves.

[Aardwolf]

What did you mean in the previous reply with "That may be true for multi-volume scenario"?

Did it mean multi volume is NOT hassle-free with UEFI?

Thanks

[josteink]

UEFI has no issues with multi-volume setups. They are hassle free.

My focus one single volume setups was really because this is where traditional legacy BIOS boot gets messy and unreliable if you want to setup dual/multi-booting, and UEFI is objectively superior in every way.