GRUB2 is the next generation of the GRand Unified Bootloader (GRUB). Ubuntu has used GRUB2 as the boot loader since 9.10 (Karmic Koala). Commonly referred to as simply "GRUB".

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221
votes
31answers
234k views

How do I remove or hide old kernel versions to clean up the boot menu?

Every time I install a new Linux kernel, it gets left in the grub_config, making the boot menu longer each time. I know I can manually search through the installed packages and remove them. Does ...
139
votes
5answers
549k views

How do I change the GRUB boot order?

I have both Windows 7 and Ubuntu installed on a shared machine. Because a lot of the non-developers use Windows, I'd like to change the boot order to make it easier for them. Currently the boot order ...
110
votes
9answers
149k views

How can I repair grub? (How to get Ubuntu back after installing Windows?)

I installed Windows 7, which ate Ubuntu's boot file. When starting up the computer, it now goes straight to Windows, without giving me the option of booting Ubuntu. How can I get Ubuntu back?
99
votes
16answers
217k views

How do I set Windows to boot as the default in the boot loader?

How do I set the bootloader so that in my dualboot with Windows 7/Ubuntu 11.04, Windows start up as standard instead of Ubuntu?
61
votes
2answers
169k views

How do I set the grub timeout and the grub default boot entry?

In Ubuntu 12.04, how do I set the GRUB time and the default OS (that I see at boot time) as I'm dual-booting Windows 7 and Ubuntu 12.04?
50
votes
3answers
90k views

How to get to the GRUB menu at boot-time?

This issue came up recently for me (and I've been prompted to lodge it as a specific question about it): My system is not dual-boot, I run a standard Ubuntu desktop system "on the metal" (I think ...
42
votes
1answer
53k views

Dual boot Surface Pro with Ubuntu?

How could I setup a dual boot for Ubuntu and Windows 8 on my Microsoft Surface Pro with 128 GB. Note: My dual boot solution is below.
33
votes
2answers
20k views

Why this occurs error: Diskfilter writes are not supported

This message occurs when leaving the Grub menu and before the Ubuntu splash screen. How do I fix the problem to clear the message? And what doe is it mean? error: Diskfilter writes are not ...
31
votes
1answer
37k views

How do I boot into a root shell?

When booting to the graphical desktop fails we sometimes are recommended to boot into a "root shell" or to boot in "recovery mode". How do I do that?
31
votes
5answers
396k views

Recovering from 'grub rescue>' crash

I did a dumb thing... I forgot that Ubuntu 10.04 (Lucid Lynx) switched to GRUB 2 which puts a ton of *.mod files (kernel modules) in /boot/grub. I thought they were soundtrack files put there ...
30
votes
3answers
45k views

How do I add a kernel boot parameter?

I need to add the boot parameter foo=bar to my kernel. How can I do this once for testing, and permanently if testing was a success?
27
votes
5answers
114k views

I can't get grub menu to show up during boot

After trying (and failing) to install better ATI drivers in 11.10, I've somehow lost my grub menu at boot time. The screen does change to the familiar purple colour, but instead of a list of boot ...
27
votes
5answers
58k views

How can I show or hide boot messages when Ubuntu starts?

Is there a way to easily turn on/off showing the boot messages (loading the services) when Ubuntu starts? Is it something in Grub2? I am running Lucid.
26
votes
6answers
113k views

Recovering GRUB after installing Windows 7? [duplicate]

Possible Duplicate: How can I repair GRUB? (How to get Ubuntu back after installing Windows?) I installed Windows 7 after it crashed, and now I am unable to boot Ubuntu. Ubuntu ...
26
votes
5answers
7k views

Decrease GRUB timeout

The GRUB timeout is 8 seconds. Can this be turned down to 2 or 3 seconds? What is the best way to do this?
25
votes
0answers
4k views

How to remove the unwanted entries from the boot menu? [duplicate]

Possible Duplicate: Is there a way to remove/hide old kernel versions? When my system boots up, a big list of some 6 options are shown other than the Windows OS option. They are like : ...
23
votes
3answers
99k views

How do I boot into single-user mode from GRUB?

After changing a few lines in xorg.conf, I can no longer boot Ubuntu (I assume it breaks when trying to load up X), so I need a way to boot into a single-user mode. However, there seems to be zero ...
23
votes
2answers
18k views

How to get grub2 to remember last choice?

Grub2 - Community Ubuntu Documentation says the following: Saving an OS can be achieved by running sudo grub-set-default if DEFAULT=saved is set in /etc/default/grub. It may also be saved if ...
23
votes
1answer
14k views

What do I select for “GRUB install devices” after an update?

After running Update Manager, a debconf window (titled "Configuring grub-pc"), popped up, requiring me to select the appropriateGRUB install devices for my system. I've made no changes to grub or ...
22
votes
2answers
9k views

How do I apt-get -y dist-upgrade without a grub config prompt?

Per Make apt-get (or aptitude) run with -y but not prompt for replacement of configuration files? I did the following: ec2run ami-3c994355 --region us-east-1 -n 1 -t m1.large -z us-east-1d On the ...
22
votes
4answers
46k views

How do I run update-grub from a LiveCD?

Okay, so I did something stupid. I was trying to clean up my Grub entries, and accidentally removed all of my Linux kernels from Grub (they're still on the hard drive). So now, obviously, Grub ...
21
votes
6answers
250k views

Fixing GRUB error: “error: unknown filesystem” [duplicate]

When booting into Ubuntu, I'm getting the following error with a grub rescue shell following it: Error: unknown filesystem. grub rescue> I'm not exactly sure what I did. I believe I installed ...
21
votes
2answers
12k views

How to disable Grub's menu from showing up after failed boot

I am performing a test in which I hard-reboot a machine with Ubuntu during its boot sequence (just before login prompt appears). After the reboot, GRUB's menu shows up with no timeout (not its ...
20
votes
2answers
77k views

How do I set 'nomodeset' after I've already installed Ubuntu?

I know that editing the boot options line and adding 'nomodeset' solves my laptops problem during LiveCD mode, what I don't know is how to set it at boot up through Grub2 after I've installed Ubuntu. ...
20
votes
2answers
13k views

How can I force Ubuntu to boot on a stuck boot menu?

I have Ubuntu Server 11.04, but it is headless (no monitor). The only way I want to be able to access it is remotely via SSH. But, sometimes, say after a power loss, when the server restarts, it will ...
19
votes
5answers
5k views

How do I investigate boot and partition issues?

My machine won't boot, or won't choose the right operating system when I choose it in the grub menu, what information do I need to provide in my questions so people can help me?
19
votes
7answers
48k views

Grub does not show a Windows 8 option after dual boot

So, I've successfully dual-booted my Windows 8 machine with Ubuntu 12.04 . However, I still don't have a convenient method of choosing what OS to load at boot time. After installing Ubuntu, my ...
19
votes
4answers
64k views

How do I reset a lost password (using recovery mode requires me to type the password)?

I need to reset my password. I have followed these steps: How do I reset a lost Administrative (root) password? However, then I go to "root" or "netroot" recovery options, it tells me: Give root ...
19
votes
4answers
103k views

Grub rescue - error: unknown filesystem

I have a multiboot system set up. The system has three drives. Multiboot is configured with Windows XP, Windows 7, and Ubuntu - all on the first drive. I had a lot of unpartitioned space left on the ...
18
votes
2answers
4k views

How can I see what happens during the boot process?

On my machine booting takes more than a minute which is annoying when I see that Windows 7 boots in 20 seconds. Here is what I get when the machine is booting. How can I see what happens when ...
18
votes
3answers
2k views

How do I burn multiple Ubuntu isos on one DVD?

I always find it a waste putting a 790MB Ubuntu iso on a 4GB DVD, and I was wondering how to put multiple operating systems on one DVD with a grub menu. I know it is possible, but I just don't know ...
17
votes
3answers
3k views

Why doesn't BURG replace GRUB?

BURG looks a lot better and user friendly than GRUB, at the same time it get the job done. Why Ubuntu have not switched to it?
17
votes
2answers
54k views

How can I change/convert a Ubuntu MBR drive to a GPT, and make Ubuntu boot from EFI?

I recently have upgraded my PC, my new Motherboard (ASUS M5A99X EVO) uses UEFi instead of the regular MBR option. I have a Ubuntu 11.10 installation that I did when I had my previous hardware (MSI MS ...
17
votes
2answers
21k views

GRUB2: Use maximum detected resolution?

How do I tell GRUB2 to set its resolution (and also the one passed to the kernel) to the maximum one it can detect at time of boot?
17
votes
1answer
34k views

GRUB complains of “no such partition” after installing 12:04

I have just installed 12.04. I previously had 11.10 installed, with /dev/sda6 as the install partition mounted at / and with /dev/sda1 mounted at /home. When installing 12.04, I duly selected the ...
17
votes
5answers
20k views

How to change the purple background color in grub?

How to do this manually, not installing any tools?
17
votes
1answer
26k views

What is vt.handoff=7 parameter in grub.cfg?

I wonder what vt.handoff=7 parameter does. I can not find any good man for that... BTW, if you have a nice descriptoon about : search --no-floppy --fs-uuid --set=root I would be happy :) grub.cfg ...
17
votes
4answers
44k views

Failed to get canonical path of /cow

I am trying to install Ubuntu 12.10 for quite some time, and passing hurdles one by one. Now I am in a situation as follows. I have got a PC and 10 GB HDD which will be totally dedicated to Ubuntu so ...
16
votes
6answers
11k views

How to reboot into Windows from Ubuntu?

I'm looking for a way to reboot into Windows from Ubuntu on a 10.10/Vista dual boot system. The specific use case is that I would like to be able to ssh into my running Ubuntu instance and issue a ...
16
votes
4answers
62k views

I receive the error 'grub-install /dev/sda failed' while attempting to install Ubuntu as the computer's only OS.

I am attempting to install Ubuntu on a box which was previously running Windows 7. I have also experienced the dreaded "Unable to install GRUB" error. I am not attempting to dual boot. I have ...
16
votes
5answers
197k views

Grub rescue prompt, repair grub [duplicate]

I recently repartitioned my hdd and I have damaged grub on my system. On boot I get the grub rescue prompt and I have to go through the following steps in order to boot normally: set ...
16
votes
1answer
1k views

boot up problem (14.04 + GRUB + Swap + Nvidia) - with pictures

When I start my laptop, it takes as much as 7 tries to get past the place where the swap gets mounted; if anyone is looking over my shoulder then it becomes 15 tries! My laptop is a lenovo W520 with ...
15
votes
5answers
26k views

How can I get some nice eye candy themes for Grub?

Grub is well Grub. How do I pimp it a bit with some nice themes?
15
votes
11answers
48k views

How do I hide the GRUB menu showing up in the beginning of boot?

I stopped Dualbooting and I dont want to have to choose the OS anymore and just have it load Ubuntu like normal like before? Any help is appreciated.
15
votes
6answers
42k views

How to boot live iso images?

I found that it can be done with loopback as follows menuentry "Lucid ISO" { loopback loop (hd0,1)/boot/iso/ubuntu-10.04-desktop-i386.iso linux (loop)/casper/vmlinuz boot=casper ...
15
votes
1answer
72k views

How do I boot into recovery mode?

I recently tried booting into the Grub2's menu entry "Ubuntu GNU/Linux, with Linux 3.2.0-24-generic-pae (Recovery Mode) just to see what was there. It booted successfully, but I had no idea what to ...
15
votes
8answers
31k views

Hide GRUB2 menu UNLESS you hold down Shift key: how to make this happen?

I have a Ubuntu - Windows 7 dual-boot set-up, and I would like to have it that my laptop would boot up Windows 7 unless I press down the Shift key right after boot and bring up the Grub2 menu from ...
15
votes
6answers
9k views

How to boot from an .iso file in GRUB2?

Is there a way for doing this?
14
votes
2answers
52k views

How do I safely change grub2 screen resolution?

I did a fresh install of Ubuntu 11.04 on a HP 550 Notebook. But grub2 isn't really fit in the best screen resolution that this Notebook can support (1280x800). How can I do this without using a ...
14
votes
6answers
4k views

Is there a way to manage my Grub menu options from with the GUI/desktop?

With each kernel update, a new entry is placed in Grub to provide a way to boot that specific kernel version. I have about 5 at the moment and, to be honest, once I have confirmed I can boot into the ...