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Help/Recommendations for setting up new SSD with Linux
(lemmy.world)
From Wikipedia, the free encyclopedia
Linux is a family of open source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991 by Linus Torvalds. Linux is typically packaged in a Linux distribution (or distro for short).
Distributions include the Linux kernel and supporting system software and libraries, many of which are provided by the GNU Project. Many Linux distributions use the word "Linux" in their name, but the Free Software Foundation uses the name GNU/Linux to emphasize the importance of GNU software, causing some controversy.
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Linux bootloaders discover the correct linux volume by UUID (which is in the filesystem), or PARTUUID (which is in the GPT table). It'll look at every drive, and when it sees the matching one it'll look in that partition, find the kernel & initrd, suck them into ram, and launch the kernel.
The main problem with moving drives around is - where is the EFI firmware looking for the bootloader in the first place? If you read efibootmgr, the efi data is pretty simple and very much tied to a hardware port. The EFI takes the most preferred bootloader entry, goes to that drive, and runs a file like "\EFI\grub\grubx64.efi". If that file isn't right there, the EFI isn't going to look elsewhere for it.
There is one bootloader name that EFI will pluck out of the blue and (smash the Fx key) offer to you as a boot option - "\EFI\BOOT\BOOTX64.EFI". Self booting usb installers use that, but you could use it too. Put all the other files that go along with the bootloader in with that boot folder, and rename the appropriate .efi to bootx64.efi.
One thing that I've done on odd setups is to put rEFInd on the efi partition as the boot\bootx64.efi loader. It'll do a pretty fancy job of detecting what's bootable (may need an additional filesystem_driver.efi), or even chain into grub to finish the startup.