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

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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 ...
23
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3answers
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Installing Grub 2 on a USB flash drive

MultiBootISOs is a tool that let you install Grub on a USB flash drive. I really like it because it lets me boot from ISO files and let me put a bunch of ISOs on my USB and choose which one to boot. ...
19
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3answers
31k views

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. ...
18
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3answers
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FreeNAS grub2 booting ISO

I've got usb-keys setup to multi-boot different Linux images. I wouldn't mind adding FreeNAS, and there's a doc with samples to add to grub.cfg menuentry "FreeNAS-8.0.4-RELEASE-x64" { insmod ufs2 ...
16
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1answer
14k views

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 ...
15
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4answers
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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 ...
14
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5answers
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What is the difference between LILO and GRUB?

I am running a web server under Debian and I currently have GRUB installed. Should I consider using LILO instead of GRUB? And what are the advantages of each?
13
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1answer
853 views

mistakenly deleted /boot folder and rebooted

I mistakenly deleted the /boot folder from my filesystem, rebooted, and all I get now is this: error: file '/boot/grub/i368-pc/linux.mod' not found. grub rescue>
13
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5answers
581 views

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 ...
13
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3answers
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Chainload two Grub2 installations

This is really getting me down. I have Gentoo and Ubuntu, both with Grub2. Gentoo has a dedicated /boot partition, while Ubuntu does not. I have a menuentry in Gentoo's /etc/grub.d/40_custom to boot ...
11
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1answer
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Where can I learn more about how to use the GRUB `ntldr` command (module?)

I recently stumbled across the GRUB ntldr module. Apparently one of the things it can be used for is as an alternative to chainloader to boot the NT >= 6.0 versions of Windows as in the example ...
11
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4answers
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Enabling IOMMU in the kernel for graphics card pass-through

Short question: How can I turn on the intel_iommu setting in the Linux kernel? I run a Debian host, using the grub2 bootloader. Documentation I've seen says to edit /boot/grub/menu.lst, which seems ...
10
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2answers
444 views

What are these commands for?

Yesterday I had to install a Windows with its Grub override. Well, it's not the first time I had to fix Grub, so I used LiveCD, mounted the root partition (I don't have boot, just / and home) and ran ...
10
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4answers
6k views

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 ...
9
votes
3answers
4k views

How do I begin with building a Linux system from scratch?

I tried to make an operating system with my on custom built kernel. It didn't work out too well. I am using Ubuntu and have downloaded Linux 3.2.7 from kernel.org . I am not trying to change the ...
9
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2answers
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How to check on which drives grub2 has actually installed an MBR?

I'm on a Debian/Squeeze system (with a history going back to at least Woody) which was upgraded to grub2 as part of the Squeeze upgrade. All works well, but I'm about to mess with the disk ...
9
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2answers
9k views

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?
9
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1answer
5k views

grub error “superfluous RAID member” on update-grub

My system (wheezy/sid: 2.6.32-5-amd64 #1 SMP x86_64 GNU/Linux) is running fine - I'm just wondering what some messages mean. I have two mdraid arrays running up on my system. Here's cat /proc/mdstat: ...
9
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2answers
7k views

How do I prevent GRUB from using/starting any graphical UI?

I have a problem with an older Laptop (Fujitsu Siemens LifeBook S6010, to be precise) and an Ubuntu (10.10, Xubuntu desktop) installation (fresh install). During installation the graphics hardware ...
8
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4answers
516 views

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 ...
8
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3answers
2k views

How should I configure grub for booting linux kernel from a USB hard drive?

I have a laptop hard drive in an external enclosure which I use as a large pendrive. For an added twist, I have installed Linux on it, so I can boot any machine with my distribution of choice (e.g. ...
8
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2answers
5k views

Chainload syslinux from GRUB2 - show syslinux.cfg menu

I am using a Clonezilla live USB disk to reimage systems. In accordance to what is explained in ...
8
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2answers
7k views

Poor TTY resolution with nVidia driver

The resolution of the TTY1-6 is poor ~ 640×480 Ubuntu 11.10 | Grub2 | nVidia | NVIDIA GT215 Board I went through the process on this site and after the edit the GRUB menu appears in the correct ...
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5answers
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Arch GRUB asking for /run/lvm/lvmetad.socket on a non lvm disk

I am running this script based on the ArchWiki setup procedure. It fails on the GRUB configuration step I am using the archlinux-2013.12.01-dual.iso inside VMware Player with 1 GB ram, sda is 810 ...
7
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2answers
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Is Grub installed to all the MBR of a RAID array by default by the Debian Installer?

If I use the Debian Stable (Squeeze) Installer to install Debian, booting from a RAID1 pair of drives, does it write grub to the MBR of both drives - if not, how should I best protect against a drive ...
7
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1answer
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booting qemu/kvm directly from a file system

Having used Xen and its pygrub for a while, I'm now trying to do something similar with KVM/qemu. Basically, I have a LVM logical volume (though that could as well be a file) that contains the root ...
7
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1answer
8k views

How do I add PC BSD / FreeBSD to Grub 2 boot loader?

I have Ubuntu 10.04 installed as my primary operating system, and I installed PC BSD in a different partition: /dev/sda4 without installing it's boot loader. I figured out that I need to edit ...
7
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3answers
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Arch linux : pacman does not work when chrooting

I have Ubuntu installed on my computer. I decided to install Arch linux, but I skipped the part about Grub installation as it is already installed. Seeing that Arch does not show up in Grub's menu ...
7
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2answers
270 views

Installing other Linux in an encrypted disk

I recently got an SSD to replace my laptop's HDD and decided to change and use "full disk" encryption. I created a small unencrypted partition for /boot and an big encrypted LUKS partition where I ...
7
votes
2answers
600 views

Determine what program is in my MBR code

I've done a lot of partitioning / dual booting on my Macbook Pro. Right now I have Mac OS X installed along with Ubuntu 12.04, with Grub installed on the Ubuntu partition. I am wondering - what is ...
6
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1answer
355 views

How can I prevent someone from gaining root access through the bootloader?

On Ubuntu 10.10 I can login as root without the root password by replacing ro quiet splash with rw init=/bin/bash. How can I secure my machine and disable this backdoor?
6
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1answer
110 views

What Linux kernel features does os-prober require to find a Windows 8 installation?

I built a new custom Linux kernel using make localmodconfig and after booting the new kernel, update-grub doesn't detect my Windows 8 installation. My distro kernel (with tons of modules I don't ...
6
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1answer
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How do I update grub in Arch Linux

In Ubuntu we use below command to update grub 0.98 : # update-grub But how do I update grub version 2.00 in Arch Linux ? `
6
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2answers
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Grub 'incompatible license' error

The other day, I was using a laptop for general desktop use when its keyboard began to act up. Most of the keys on the keyboard's right side stopped working entirely and key combinations such as Ctrlu ...
6
votes
1answer
2k views

EFI boot to Linux on a MacBook Pro

8,3 MacBook Pro 2011, running Ubuntu 11.10 amd64. Here's the situation. Screen backlight and a few other things only work if booting in EFI, so I need to boot Ubuntu in EFI to get things working. ...
6
votes
1answer
132 views

How to Pass High Resolution from GRUB2 to FreeBSD?

I boot FreeBSD-10-RELEASE from GRUB2. I have set up the GRUB2 boot menu to display very nicely at my laptop's max resolution of 1024x768x32. I know it's possible to pass this resolution to the boot ...
6
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1answer
2k views

Booting a file system image from a HDD using GRUB2 with persistence

How do I preserve changes I make to files when running an operating system that is booted - using GRUB2 - from a file that contains a file system. I managed to get GRUB2 to boot an image file that ...
5
votes
5answers
812 views

Bootstrapping a DSL installation onto a machine with no BIOS boot support

I have a vintage 2001 laptop (Vaio R505) which is very hardware limited. Fortunately there is much that works, but I can't figure how to make it work better. The two biggest constraints are 256MB RAM ...
5
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3answers
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How to make grub work again after drive reassignment?

My config: opensuse 11.4, boot partition at pendrive and hard drives with partitions sda1, sda2, sdb1. Today I changed chassis for my computer, and by mistake I attached second drive to SATA 3 ...
5
votes
3answers
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Installed Centos 7 after Windows and can't boot into CentOS

I wanted to setup a dual boot for Windows 7 and CentOS 7 I had a Windows 7 machine with 500GB disk. I shrank the Windows partition to provide space for CentOS 7 (roughly 230GB). I created a USB ...
5
votes
4answers
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Grub error 15 (file not found)

I'm trying to fix a problem with a new installation. I'm running this existing distro (Ubuntu) from /dev/sdb with a new OS, Gentoo, installed on /dev/sda. I'm glad I took the trouble of setting these ...
5
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2answers
3k views

How to recreate EFI boot partition?

I've installed Fedora on my machine with / partition, swap partition and ESP partition for EFI booting. Now, I was installing Elementary OS instead of Fedora. I have formatted the / partition ...
5
votes
2answers
4k views

After Arch Linux install it just shows the text “No bootable device found”

I've been trying to install Arch Linux. After the installation, it shows the BIOS screen and after that there just comes a message that says "No bootable device found". I have retried the whole ...
5
votes
2answers
6k views

How do you dual boot Debian and FreeBSD using GRUB2?

I've been trying to install FreeBSD alongside my Debian installation in a single partition. All examples readily present on the Internet had shortcomings: Some required chainloading the FreeBSD ...
5
votes
1answer
411 views

Grub-install: embedding is not possible in Bios/GPT

I am struggling with setting up an encrypted NAS for some days now. The basic plan is to have btrfs on lvm on luks on raid1 with lvmcache in writeback mode thrown in for the root partition to reduce ...
5
votes
1answer
416 views

How to specify an ISO as the location of root filesystem for GRUB?

I'm trying to understand the Debian "booting from Hard Disk" installation manual. The process is as follows: I copy a kernel image, a ramdisk initrd and an ISO with installer to the hard drive and ...
5
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2answers
2k views

How to manually manage grub.cfg for Grub2?

I am setting up my system. The features of it are: GPT partition table (not sure how important this is) Triple boot - Gentoo, Debian and Mint. Custom kernel (kernel git repo) shared amounst distros. ...
5
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1answer
3k views

Fedora 17 : Cannot open font file True

Each time I login to Fedora 17, no GUI, just a console, I notice this error: Cannot open font file True I have followed some tutorial on web to fix this problem, but still cannot. Here some steps ...
5
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3answers
884 views

Two EFI disks with Grub2

I bought two SSD disks and as usual I though that installing Windows on a completely separate disk would be the easiest solution, but I can't find any tutorials for dual booting with grub2 (efi). All ...
5
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4answers
785 views

Is there an easier way to manipulate GRUB 2 entries?

Using GRUB 2 is harder than GRUB 1 for these use cases: It looks like if I want to reorder GRUB 2 menu entries appear in the selection window, I have to rename the files in "/etc/grub.d/" directory. ...