ubuntu how to repair grub

[Solution] How to Fix GRUB

1. Configure all the pending packages.sudo dpkg --configure -a
2. Fix the broken packages.sudo apt install -fy
3. Remove the current grub.sudo apt purge -y grub
4. -common grub-common:i386 shim-signedThis may give you a warning that...
5. sudo apt install -y grub-pcAfter running this command, it will ask you to point the current sdXY to install the...

Full Answer

How to restore GRUB bootloader in Ubuntu?

Using the Ubuntu Alternate CD

• Boot your system from the Ubuntu Alternate CD.
• When the Ubuntu splash screen comes up with the boot: prompt, type in rescue and press enter.
• Choose your language, location (country) and then keyboard layout as if you were doing a fresh install.
• Enter a host name, or leave it with the default (Ubuntu).

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How can I repair GRUB?

• Boot from the live CD or live USB, in "Try Ubuntu" mode.
• Determine the partition number of your main partition. ...
• Mount your partition: sudo mount /dev/sda2 /mnt #Replace sda2 with the partition from step 2 If you have a separate /boot, /var or /usr partitions, repeat steps 2 and 3 ...

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How to restore Grub After installing Windows 10?

Solution 2: Resetting the BIOS Settings

1. Turn off your computer and wait for a couple of minutes, then give it a fresh restart.
2. Now, press F2 and repeat the process till you see the System Screen Window. The function key may vary from system to system.
3. Now with the help of the Right Arrow Key go to the Exit menu bar. ...
4. After you pressed the Load Optimized Device option, hit the Enter button. ...

How to repair Ubuntu easily?

launch Boot-Repair from either : the Dash (the Ubuntu logo at the top-left of the screen) or by typing 'boot-repair' in a terminal Then click the "Recommended repair" button.

How do I repair grub files?

ResolutionPlace your SLES/SLED 10 CD 1 or DVD in the drive and boot up to the CD or DVD. ... Enter the command "fdisk -l". ... Enter the command "mount /dev/sda2 /mnt". ... Enter the command "grub-install --root-directory=/mnt /dev/sda". ... Once this command completes successfully reboot your system by entering the command "reboot".

How do I fix grub in terminal?

via Partition Files CopyBoot to the LiveCD Desktop.Mount the partition with your Ubuntu installation. ... Open a terminal by selecting Applications, Accessories, Terminal from the menu bar.Run the grub-setup -d command as described below. ... Reboot.Refresh the GRUB 2 menu with sudo update-grub.More items...•

How do I restore grub loader?

To remove it:Hit Windows + X and select Disk Management .Find the Ubuntu partition. It will probably be a large partition without a drive letter.Be sure you have the correct partition!Right-click the partition and delete or reformat it with a Windows filesystem.

How do I uninstall and reinstall grub?

Uninstalling GRUB 2Open a terminal: Applications, Accessories, Terminal.Optional: Make backup copies of the main GRUB 2 directories and files. sudo cp /etc/default/grub /etc/default/grub.old. ... Remove GRUB 2. sudo apt-get purge grub-pc. ... Install GRUB 0.97. ... With grub installed, the user must still create the menu. ... Reboot.

How do I fix corrupted grub in Linux?

The solutionTo fix the problem execute from grub command line: ... Restore boot partition on hd0,0 (first partition on first disk) as in above example from find command. ... Then setup grub on first disk (hd0) – as in above example boot stage1 is located on hd0. ... After command will succeed reboot the server.

How do I fix Ubuntu when it wont boot?

If Ubuntu is not booting, work through these five steps:Check for bootable devices.Is the GRUB bootloader working?Repair the bootloader menu.Reinstall Ubuntu.Replace faulty hardware.

What are the grub rescue commands?

GRUB Rescue CommandsCommandDescriptionExampleconfigfileLoad a configuration file.configfile (hd0,1)/boot/grub/grub.cfginitrdLoad the initrd.img file.initrd (hd0,1)/initrd.imginsmodLoad a module.insmod (hd0,1)/boot/grub/normal.modloopbackMount an image file as a device.loopback loop0 (hd0,1)/iso/image.iso7 more rows•Dec 2, 2021

How do I use grub command line?

Booting From grub> The first line sets the partition that the root filesystem is on. The second line tells GRUB the location of the kernel you want to use. Start typing /boot/vmli , and then use tab-completion to fill in the rest. Type root=/dev/sdX to set the location of the root filesystem.

How do I remove grub from BIOS?

Originally Answered: How do I remove GNU grub and install windows boot loader? It's very simple. Just press f12 when booting screen appears, then go to BIOS. On that page at the bottom you will see an option of reset .

How do I install boot Repair?

Getting Boot-Repair The easiest way to use Boot-Repair is to create a live-USB disk of Boot-Repair-Disk (a disc starting Boot-Repair automatically), and boot on it. Remark : it is recommended to install the ISO on a live-USB (eg via UnetBootin or LiliUSB or Universal USB Installer).

How do I manually install GRUB bootloader?

Installing GRUB2 on a BIOS systemCreate a configuration file for GRUB2. # grub2-mkconfig -o /boot/grub2/grub.cfg.List block devices available on the system. $ lsblk.Identify the primary hard disk. ... Install GRUB2 in the MBR of the primary hard disk. ... Reboot your computer to boot with the newly installed bootloader.

What is GRUB boot loader in Ubuntu?

The GRUB (Grand Unified Bootloader) is a bootloader available from the GNU project. A bootloader is very important as it is impossible to start an operating system without it. It is the first program which starts when the program is switched on. The bootloader transfers the control to the operating system kernel.

How to reinstall a broken grub?

There are a lot of methods in Linux that can be used to re-install a broken grub, some can involve the ability to work and restore the boot loader by using the Linux command line and others are fairly simple and implies booting the hardware with a Linux live CD and using the GUI indications to repair the damaged boot loader.

How to boot Ubuntu live image?

1. After you’ve downloaded and burned the Ubuntu ISO image, or created a bootable USB stick, place the bootable media into your appropriate machine drive, reboot the machine and instruct the BIOS to boot into Ubuntu live image. Machine Boot Menu. 2.

Where to install bootloader?

Usually, you should install the boot loader on your first machine hard disk MBR, which is / dev/sda in most cases. The installation process of GRUB will start as soon as you hit the Enter key.

Can Ubuntu 16.04 rescue grub?

This procedure has been successfully tested on an Ubuntu 16.04 server edition with the Grub boot loader damaged. However, this tutorial will only cover Ubuntu server GRUB rescue procedure, although the same procedure can be successfully applied on any Ubuntu system or on the majority of Debian-based distributions.

How to install boot repair in Ubuntu?

To start the installation of Boot Repair in the Ubuntu live environment, open up a terminal window. To open up a terminal window in the Ubuntu live environment, press the Win key on the keyboard and search for “terminal.”. Or, press Ctrl + Alt + T on the keyboard.

What does it mean when a boot repair screen appears?

When it does start up, a loading screen will appear. This loading screen indicates that Boot Repair is scanning your computer for any traces of Grub. Please allow it to scan.

How to make a live USB for Ubuntu?

Step 1: Go to another working PC that you can use in place of your broken Ubuntu PC. You will need a PC to create a bootable Ubuntu live USB. Once on the spare PC, head over to Ubuntu.com, click on the “Download” button.

How to download Ubuntu on a PC?

Once on the spare PC, head over to Ubuntu.com, click on the “Download” button. Then, find the “Desktop” section on the website, and click on it. Then, download the latest version of Ubuntu to your PC.

Can you repair a grub bootloader?

Note: although this guide assume s the user is repairing the Grub bootloader for Ubuntu, Boot Repair can fix almost any Linux operating system running Grub. Feel free to follow along with the guide even if you’re not an Ubuntu user!

What happens after a GRUB bootloader is repaired?

After a successful GRUB bootloader repair, a ‘Boot successfully repaired’ message will appears on your screen. It will provide a URL where you will find all the information regarding the boot repair. You can now reboot and system and boot your system with the repaired GRUB bootloader.

Why is my Grub file damaged?

One of the major reasons for damaging the GRUB files is having multiple bootloader directories for different distributions and operating systems. Using Ubuntu and Windows together in a dual boot system is commonly used very often.

Why use Ubuntu server ISO?

Using a Ubuntu server ISO file to repair a Ubuntu desktop or server is clever because the ISO server file size is smaller than the desktop LTS file. It takes a short time to make a bootable file and quick to boot. Here, we will see how to use the Ubuntu server ISO file to recover and repair the GRUB bootloader file on Ubuntu.

What do you need to do when a USB stick boos?

When it boos successfully, you need to select the language, keyboard format, and other configurations to start with the live USB stick.

Can you run a live test on Linux?

Final Words. One of Linux’s ISO files’ best features lets you look at it before installing it on your machine. You can run a live test on your system; later, you can choose if you want to install it or not. This feature is not only helpful to test drives; it can help to recover your operating system if you accidentally remove or mess up with ...

Can you repair a Ubuntu bootloader?

Till now, we have used a live CD/USB disk of the Ubuntu desktop/server to repair the GRUB bootloader. There are options to repair the bootloader with a dedicated GRUB bootloader ISO file. You can download the GRUB loader ISO file and make it bootable instead of using the desktop/server ISO file.

What causes a GRUB to break?

There are many possible causes to a GRUB break: Windows writing on the MBR, DRM preventing GRUB from installing correctly, installer bug, hardware change...

How to find EFI partition in Ubuntu?

If Ubuntu is installed in EFI mode ( see this answer if you're unsure ), use sudo fdisk -l | grep -i efi or GParted to find your EFI partition. It will have a label of EFI. Mount this partition, replacing sdXY with the actual partition number for your system:

How to launch Gnome after installation?

After completing the installation you can launch it from System->Administration->Boot-Repair menu if you use Gnome, or search "boot-repair" in the dash if you use Unity. Then follow the following screenshots:

Can Windows see Linux partitions?

1. Windows does not see Linux formatted partitions. You need to use gparted from a liveCD and create a primary partition formatted NTFS with the boot flag. Some have had issues if the new primary partition is after the extended partition as Windows does not always reset partition table correctly.

Does Windows break GRUB?

Windows breaks grub all the time its a really common issue and one ive had to deal with myself. The answer is still good and should fix the problem.

Is it necessary to install GRUB2?

Sometimes giving GRUB2 the correct configuration for your partitions is not enough, and you must actually install it (or reinstall it) to the Master Boot Record, which step 8 does. Experience helping users in chat has shown that step 8 is sometimes necessary even when no error messages are shown.

What is GRUB 2?

Grub 2 was a long awaited and very important upgrade over the previous version of the most popular and widely used boot manager in existence. Support for new filesystems, themes, improved splash capability, better internationalization, power-pc booting, dynamic module loading and scripting support. All this is great, but things can still go wrong and break unexpectedly. This basically means that a bootable partition (operating system) may become inaccessible and this is why Grub v2 offers a powerful rescue mode. Now using this mode, may not be exactly a walk in the park for most inexperienced users out there, so here's a guide on how to easily fix your Grub with the Boot Repair tool.

Where are Grub 2.0 settings stored?

If all of the above fails, keep in mind that Grub 2.0 settings are stored in /etc/default/grub, so if you open it with a text editor as root, you will be able to edit the options and enable or disable the various settings. In this configuration file, you will find some options that are not available in Boot Repair, so knowing that what you do in the tool reflects here is important. For any changes to take effect, you should “Save” the file and run “update-grub” afterwards to update the /boot/grub/grub.cfg file that is were Grub reads its settings from. Good luck!

What is boot repair?

Boot Repair is a simplistic but powerful enough tool that promises to repair the most frequent problems that may arise on a Grub installation. The tool is usually not available through the default repositories of most distributions out there, so users will have to install it from 3rd party repositories. One example that contains the latest version of the software (there are many others too) is the yannubuntu ppa. Ubuntu/Mint/ElementaryOS users may install this tool by typing the following commands on a terminal:

GRUB Boot Issues

The most common reason for GRUB not booting into the operating system is another OS's bootloader overwriting GRUB boot configuration. The problem occurs during an attempt a dual boot with an existing Linux installation. Another reason is the accidental removal of GRUB configuration files.

GRUB Rescue Commands

Below is the list of the commonly used GRUB Rescue commands. Use the commands in the prompts mentioned in the previous section.

Fixing Boot Failure

This tutorial covers two ways to resolve GRUB boot issues, using the GRUB Rescue prompt, and the Boot Repair tool.