Questions tagged [grub2]
GRUB 2 is the next generation of the GRand Unified Bootloader (GRUB). Ubuntu has used GRUB 2 as the boot loader since 9.10 (Karmic Koala). Commonly referred to as simply "GRUB".
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How do I remove 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 ...
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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 ...
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How to get to the GRUB menu at boot-time?
My system is not dual-boot, I run a standard Ubuntu desktop system "on the metal" (I think running it in a VM is the same).
Pressing c while booting does not cause the GRUB menu to appear (which I ...
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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?
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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?
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How do I set the grub timeout and the grub default boot entry?
In Ubuntu 12.04 (or above), how do I set the GRUB time and the default OS (that I see at boot time) as I'm dual-booting Windows (7/8) and Ubuntu (12.04 or above)?
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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?
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Uninstall GRUB and use Windows bootloader
I have Windows 8 pre-installed, and then I installed GRUB with Ubuntu. Ubuntu is not my thing, so now I want to remove it along with GRUB. From what I have learned, with UEFI, GRUB does not overwrite ...
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Set "older" kernel as default grub entry
I installed a mainline kernel for testing purposes. I would like to set grub to boot from the older kernel by default.
I know I can set the GRUB_DEFAULT=0 setting for the first page of grub but how ...
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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
...
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How do I re-run boot loader?
Running sudo apt-get -f install said that The link /vmlinuz.old is a damaged link and:
you may need to re-run your boot loader[grub]
Here's the full output:
user@chrubuntu:~$ sudo apt-get -f ...
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How do I set 'nomodeset' after I've already installed Ubuntu?
I know that editing the boot options line and adding 'nomodeset' solves the problem of my laptop during LiveCD mode, what I don't know is how to set it at boot up through Grub2 after I've installed ...
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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 ...
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What is the difference between GRUB_CMDLINE_LINUX and GRUB_CMDLINE_LINUX_DEFAULT in /etc/default/grub
I'm troubleshooting a fn-key brightness control problem on my laptop, so I'm wading through a lot of config options in /etc/default/grub, as you can imagine. However, it's raised a question for me:
...
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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 10.04.
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Windows 10 upgrade kills grub and boot-repair doesn't help
I've just upgraded to Windows 10 from Windows 8.1 on my partitioned laptop that has Ubuntu 14.04 installed. Grub no longer appeared on boot so I ran boot-repair from an Ubuntu liveUSB. This didn't ...
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How can I boot with an older kernel version?
The latest kernel is causing problems with my sound, which worked fine with an older version. As I have only Ubuntu installed, Grub is not getting displayed while booting. How can I manually choose my ...
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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 ...
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GRUB does not detect Windows
I have finally installed Ubuntu on my second drive. When I start my computer GRUB only offers me to boot Ubuntu, not Windows 7. What needs to be done so that I can choose between Ubuntu and Windows in ...
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Diskfilter writes are not supported > What triggers this error?
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 ...
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How can I reinstall GRUB to the EFI partition?
I want to reinstall GRUB 2 and I found these instructions:
How to Repair, Restore, or Reinstall Grub 2 with a Ubuntu Live CD or USB.
In my case, the boot loader is installed in the EFI partition. If I ...
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How to return from grub prompt to the grub menu?
If you press escape in grub menu you end up at the grub command prompt.
My question is, how can I go back to the menu, without rebooting?
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Can I boot a Live USB fully to RAM, allowing me to remove the disk?
I have a live USB made with the standard Ubuntu disk image creator for 16.04 LTS. In the current state, I can boot to this disk, but it still requires the original USB to run properly at all times.
...
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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?
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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 doesn'...
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How to safely change grub2 screen resolution?
grub2 isn't really fit in the best screen resolution that my laptop can support (1280 x 800).
How can I do this without using a third party application ?
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16.04 new installation gives grub-efi-amd64-signed failed installation /target/ ubuntu 16.04 at the end
I am installing Ubuntu 16.04 in an Intel NUC computer with UEFI enabled. I am using an SSD from another computer. During the installation I chose Erase the disk and make a new full install
At the end ...
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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 ...
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Windows 10 upgrade led to grub rescue
I was dual-booting Windows 7 and Linux Ubuntu on my desktop, and today is the day they gave out free Windows 10 upgrades. How exciting! I got the update, and it was installing, and I left to go take ...
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GRUB rescue problem after deleting Ubuntu partition! [duplicate]
After I deleted my Ubuntu partition, I rebooted my computer and I only get a prompt:
grub rescue >
The command ls lists
(hd0) (hd0,msdos5) (hd0,msdos3) (hd0,msdos2) (hd0,msdos1) (hd1) (hd1,...
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How to fix "error: unknown filesystem. grub rescue> [duplicate]
I get this error:
Error: unknown filesystem.
grub rescue>
I'm not exactly sure what I did. I believe I installed Ubuntu over Windows on my Acer netbook. I then tried to install Linux Mint, but it ...
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How do I hide the GRUB menu showing up at the beginning of boot?
I stopped dual booting and I don't want to have to choose the OS any more. I want to boot into Ubuntu 12.04 directly without seeing the GRUB menu.
How can I achieve that?
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How to secure my laptop so that hacking by physical access is not possible?
I messed up my system earlier, I was greeted with a black screen, when booting in to Ubuntu. When I started up my laptop, I selected the recovery option from the grub menu, and chose fallback at root ...
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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 partitions ...
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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 ...
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What is the difference between update-grub and update-grub2?
I'm making some changes on my grub file under /etc/default/grub. In some tutorials I have seen sudo update-grub and others sudo update-grub2. What is the difference?
user23907
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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 ...
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How can I edit my Grub bootloader entries (Hide, Rename, Remove)?
So basically I have a pretty flooded Grub bootloader, with older linux versions, 3 operating systems and memtests. What I want is to leave the operating systems only. I need to know how to do it ...
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error: file '/grub/i386-pc/normal.mod' not found
error: file '/grub/i386-pc/normal.mod' not found.
grub rescue>
What can I do? I just sit and stare at it.
I found my old netbook (Dell Inspiron 1010) which I have not used for about four years. ...
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How do I find the boot parameters used by the running kernel?
Is there a way to find out with what parameters did the kernel boot?
For example if I specify noexec=off at the grub command line? Can I see this sort of info after the system has finished booting?
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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 ...
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Add Windows 10 to GRUB OS list
I recently got a computer from school. It came with Windows 8.1 installed. I then installed another copy of Windows 8.1 (so it would use the built-in Windows Pro license) and upgraded it to Windows 10....
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How to know the version of GRUB
How do I find the version of GRUB that is running in a particular version of Ubuntu? I want a terminal command that tells me.
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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.
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How to list GRUB's "menuentries" in command-line?
Is there a way of retrieving list of "menuentries" titles of GRUB?
I need a results in a format that grub-set-default will accept. eg.
"Ubuntu"
"Memory test (memtest86+)"
etc.
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How can I add the Memtest86+ options back to the Grub menu?
If using UEFI Please see this question, "Can I boot memtest86+ if I'm using UEFI?"
After having installed the 64bit version of Ubuntu 12.04 on my Lenovo B570 I ran into the same problems I had when ...
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How to fix a grub boot error : "symbol 'grub_calloc' not found
Just ran the latest batch of updates on 20.04 (Xubuntu), and now I'm getting a GRUB error:
symbol 'grub_calloc' not found
I'm dropped into the 'grub rescue' shell, but have no idea what to do there ...
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PCIe Bus Error: severity=Corrected, type=Physical Layer, id=00e5(Receiver ID)
I have Ubuntu 16.10 (although the same happened on 16.04) on a dual boot with Windows 10. I noticed some time ago that my kern.log file was getting pretty big (10GB or more) so I decided to check it. ...
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Ubuntu 16.04 slow boot (apt-daily.service)
My boot is horribly slow, and I don't know why.
$ systemd-analyze
Startup finished in 10.975s (kernel) + 49.732s (userspace) = 1min 708ms
$ systemd-analyze blame
34.971s apt-daily.service
...
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Unable to boot into Windows after installing Ubuntu, how to fix?
I installed Windows on my computer, followed by an installation of Ubuntu. However, now I'm unable to boot into my Windows install.
What can I do to fix this?
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