Part 4: [Political Upheaval] Who is the ruler of this PC? The battle for OS boot supremacy (Coup d'état) edition.
Invasion of the internal SSD
The success with the USB SSD lured me into a deeper "abyss." If it's this fast externally, I could reach even greater heights by pouring it directly into the internal NVMe (M.2 SSD).
The agility of having everything contained within the laptop (LIFEBOOK U9310/D) alone. "Since it works on USB, internalizing it should be easy." That arrogance dragged me into a quagmire of a battle.
A death match with 12 partitions
The initial plan was a simple dual-boot of Windows 11 and ChromeOS. I made full use of Brunch's installation options, attempting to install it by specifying a particular partition. "I ran it with the options, but it won't install correctly."
ChromeOS has a special structure that holds as many as 12 partitions inside it. The installer keeps rejecting my request to create 12 frames within a single specified partition. "If I specify the entire drive, then..." crosses my mind for a moment, but if I do that, the Windows on the internal SSD will vanish without a trace. I stood frozen in a dead-end labyrinth.
The savior "Image Method" and the Windows gatekeeper
That's when I found the back door called the "loopback format (IMG installation)."
I carved out a "vacant lot" by shrinking Windows' territory (C drive) and placed the image file there. It's a "double-bottom" construction that traps 12 partitions inside this file.
"This way, Windows won't be harmed."
However, a massive wall stands in my way here. "Windows Boot Manager", the gatekeeper.
Power struggle for booting: UEFI, Boot Manager, and GRUB
Normally, when you turn on the PC, the "UEFI", the intelligence of the motherboard, wakes up first. The UEFI follows a pre-specified "boot order" to find the next partner to pass the baton to.
Windows Boot Manager (Standard Gatekeeper): It is the strongest when it comes to booting Windows, but it is extremely stubborn.
I tried to use the Windows management software "Grub2Win" to make this gatekeeper open the "hidden room (IMG file)," but the behavior was unstable and ChromeOS wouldn't wake up. Thinking back, maybe the way I wrote the configuration file was wrong,
but I want to wake up the OS more directly without going through the unnecessary process called Windows.
GRUB (Hell's Watchdog, Cerberus): In contrast, "GRUB," which came from the Linux world, is the strongest executor that can receive the baton directly from the UEFI. With GRUB, you can freely call up any OS hidden anywhere, in any file format, depending on the settings.
💡 A quick explanation: What is he fighting against? In short, the current situation is that I am taking on the super-difficult challenge of "making three residents with different personalities live together in one house without them finding out."
Windows (Windows Boot Manager): The original homeowner. High pride, does not allow others to live with him.
ChromeOS: A freeloader living inside a box called an "image file" hidden in the closet.
Ubuntu (GRUB): The "strongest manager" who arrived later. He has the authority to manage the front door key, overriding the homeowner.
Madness: Transformation into the three-headed beast "Cerberus"
Here, I played the biggest card, "the order of OS installation," to gain the initiative from Windows Boot Manager to GRUB. In the OS world, there is an absolute rule that "the one installed last seizes the initiative for booting."
I made the decision to introduce a third OS, "Ubuntu," last, just to regain the initiative. With the installation of Ubuntu, its gatekeeper, "GRUB," reigns supreme in the UEFI's top priority, pushing aside Windows Boot Manager.
"At first, I just wanted to use ChromeOS." Look at it now. I shaved off the Windows partition, hid ChromeOS in a special IMG format, and even summoned Ubuntu just to boot it. Unintentionally, my LIFEBOOK has transformed into a three-headed beast, a "Cerberus," where three operating systems monitor each other's territories.
Anticipating future capacity changes, I deliberately pushed Ubuntu to the far right (the very end) of the hard disk, completing the puzzle of intricately carved-up partitions.
What remained was the silence of late night and a pitch-black screen. "If I use Ubuntu's GRUB as the starting point, everything should connect." This conviction drives me into the final "GRUB rewrite war."