Unix and Linux Stack Exchange
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Questions tagged [grub2]

GRUB2 is the second revision of the GRand Unified Bootloader, with versions numbered 1.9x and 2.yz.

GNU GRUB (GRand Unified Bootloader) is a bootloader. It was originally intended as a common bootloader for various new operating systems conforming to the multiboot specification. Nowadays, many Linux distributions have adopted GRUB as their default bootloader.

There are two major versions of GRUB, with incompatible configuration files:

  • GRUB Legacy, with version numbers up to 0.97;
  • GRUB 2, with version numbers from 1.9x to 2.yz.

This tag is about GRUB 2. Note that versions numbered 1.9x are GRUB 2, not GRUB Legacy.

GRUB partly resides in the master boot record, so it is launched by the BIOS. GRUB2 supports both legacy BIOS and UEFI. It is able to read most filesystems, and its main job is to read the kernel and initramfs from a disk in order to place them into memory and launch the kernel.

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GRUB starts in command line after reboot

I installed Linux Mint on my laptop along with a pre-installed Windows 10. When I turn on the computer, the normal GRUB menu appears most of the time: But after booting either Linux or Windows then rebooting, I GRUB starts in command line mode, as…
Antoine Aubry
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How do I update GRUB in Arch Linux

In Ubuntu, we use this command to update GRUB: # update-grub But how do I update GRUB version 2.00 in Arch Linux?
Hamed Kamrava
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Can GRUB font size be customised?

I would like to reduce the size of the font of GRUB boot loader. Is it possible and so how?
neydroydrec
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How can I tell GRUB I want to reboot into Windows—before I reboot?

I have a dual boot Linux/windows system set up, and frequently switch from one to the other. I was thinking if I could add a menu item in one of the menus to reboot directly into windows, without stopping at the GRUB prompt. I saw this question on a…
jadkik94
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Why does Linux allow ‘init=/bin/bash’?

I recently found out that if I edit GRUB before booting and I add rw init=/bin/bash I end up with a root shell. Being in a condition that I want to understand everything I would like to know why this happens. I mean is it a bug? is it a feature? is…
triedtoomuck
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How to know if I'm booting using UEFI?

I was searching, but didn't find an obvious way to know if GRUB is using UEFI in the system boot, or the BIOS compatibility mode, or a full fledged BIOS. I found only Windows methods. Is there something in GRUB or the Kernel boot logs that shows if…
Braiam
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"warning: File system `ext2' doesn't support embedding." but my system isn't embedded either, why is grub trying?

I'm reading myself for the release of Jessie on Debian, so I'm extra cautious (should be said paranoid) about any message that can cause problems, namely warnings. My system is a desktop with Debian testing/unstable installed, on ext4 partitions for…
Braiam
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Why do most distributions chain UEFI and grub?

Most distributions install a additional boot loader on an UEFI system. UEFI itself is a boot loader, it offers a menu to select different operating systems or individual kernels. Furthermore, the UEFI settings can easily be altered with userspace…
Marco
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GRUB_CMDLINE_LINUX_DEFAULT vs GRUB_CMDLINE_LINUX

What is the difference between these two options in /boot/default/grub GRUB_CMDLINE_LINUX_DEFAULT="quiet splash" GRUB_CMDLINE_LINUX=""
Evan Carroll
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Can GRUB2 share the EFI system partition with Windows?

I have an existing Windows 7 GPT installation, which already has a EFI System partition. I am now trying to install a Linux on a separate harddisk, which is also GPT formatted. I did not find any working way to get grub booting without EFI system…
crater2150
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grub error: you need to load kernel first

I'm installing Debian 9 on an HP ProLiant DL180. When I boot from a USB drive, it opens grub2 and when I type boot it gives an error : you need to load kernel first.
mend4x
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Debian/Grub2: Moving root partition to new drive?

Does anybody have a suggestion for how to move the root partition to a new drive and set up grub2 to boot on that drive? I seem to have no luck instructing grub-mkconfig what it is I want to do (e.g. chroot'int into my new root just confuses all the…
Janus
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How to correctly set up the right GRUB 2 default menu entry?

I'm running GRUB 2.00 on a Gentoo Linux system. I compile my own kernels manually, and then I install them in /boot with make install. I have the following kernels in /boot at the moment: # ls -1…
user22304
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Is GRUB the best bootloading solution? Is there an easier alternative?

I have had some rather bad experiences with GRUB2. I could say (and have said) some nasty things about its design and development process. I especially dislike its means of update: for whatever reason it must semi-automatically update several…
user77422
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How can I prevent Windows from overwriting GRUB when using a dual-boot machine

I've been reading a lot about dual-booting, and it seems as easy as loading Windows and then loading Linux with GRUB, but everybody says that Windows loves to trash GRUB when it gets the opportunity. What are some steps I can take to prevent this…
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