Questions tagged [grub2]

GRUB (GRand Unified Bootloader) is a bootloader package to load operating systems. GRUB2 is a rewrite, and the dominant version since 2009.

Grub (GRand Unified Bootloader) is a bootloader package.

Briefly, a boot loader is the first software program that runs when a computer starts. It is responsible for loading and transferring control to the operating system kernel software (such as the Hurd or Linux). The kernel, in turn, initializes the rest of the operating system (e.g. GNU).

Official page

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Run fsck -y everytime at startup on my main partition Linux

I have an embedded linux system. I use grub2 for the boot loader. I would like to run an fsck -y /dev/sda on /dev/sda every time it boots--even when the system had a power loss and the reboot command was not used. How can I do this?
Jonathan Henson
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grub2 does not find /boot on RAID1 md0 device

I have RAID1 md0 for /boot consisting of 4 partitions (sda2, sdb2, sdc2, sdd2). I'm using GPT on 2TB HDDs, so first partitions on each disk (sda1, ...) are 1-megabyte bios_grub partitions. I also have RAID10 md1 for LVM (containing /) and RAID0 md2…
chronos
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GRUB2 not detecting OS on raid partitions

I have recently added a drive to a system and have successfully raid'ed (RAID-1) the paritions, with the exception of the boot partition. I have it ready and mirrored, but can't get GRUB2 (update-grub) to find it. System: Ubuntu 11.04 Raid…
sleeves
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Fix kernel issues in rescue mode

I have updated the kernel in a VPS Centos 7, and after rebooting, the machine is not responding anymore, including with SSH. I connected to the VPS via a temporary rescue linux machine from where I could mount the VPS filesystem: mount /dev/sdb1…
AFA Med
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GRUB fails to start kernel after net_dhcp

I originally ran into this problem trying to redeploy a machine using MAAS, but I can reproduce it just with the already-installed OS and GRUB, with Ubuntu 20.04. The machine is set up for UEFI boot. To reproduce (but see below): Boot the machine…
Bruce Merry
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How to prevent changes of GRUB_ENABLE_BLSCFG in /etc/default/grub

With Rocky Linux 8.4 (clone of RHEL 8.4) in /etc/default/grub I have GRUB_ENABLE_BLSCFG=false A “dnf update” that included grub2-tools changed it back to GRUB_ENABLE_BLSCFG=true Is there some way to prevent this from happening in future grub2-tools…
cen2rocky
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Changing your kernel in AWS appears to break boot sequence (grub config issue?)

Using Ubuntu 20.04 on AWS (ec2), I wanted to change my kernel from AWS to a generic one. When I try it the suggested way with changing the Grub Config, it stops the machine. This is because Jibri (Jitsi Video Recorder) requires the use of ALSA and…
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Chainloading syslinux using grub2

I created a syslinux/isolinux hybrid CD iso to boot either legacy bios or eufi depending on what is needed. The legacy bios part works well and has worked for many years. I am using the newest (6.0.3) version of syslinux. I used a rhel7 efiboot.img…
aseq
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CentOS7 not booting after "yum update" mokListRT fails

I updated CentOS 7 via yum update Didn't know about shim and mokutils so didn't exclude that from yum. Now I can't boot it, I can recover the files on it using another live distro (e.g. ubuntu), but when I try to run the rescue mode from a CentOS…
ZioCain
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What are the steps to convert an EBS boot volume from MBR to GPT without data loss? (Using Ubuntu)

I would like to extend one of my Ubuntu servers main/boot drive beyond 2TB. I know that I need to convert the drive to use GPT, and I'm confident that I can extend the size as needed once I'm able to convert to GPT successfully. I set up a test…
Justin Heath
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Debugging boot loop after Ubuntu 18.04

I recently did a kernel update on a s2600cp server running Ubuntu 18.04. When booting into the latest installed kernel version from GRUB. My monitor displays a blinking cursor in the top left corner, but is otherwise unresponsive. I tried ctrl + alt…
Derick
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Find out exact location of GRUB / GRUB not working after copying disk image

I prepared an Ubuntu server image with VirtualBox. To transfer the image to the server's SSD I first dded the MBR (512 bytes) and then the LVM partition (PV containing the root partition shrunk to 3GB). The server failed to boot because some parts…
code_onkel
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How to change grub2 in CentOS/RHEL7 from UUID to old style device?

With CentOS/RHEL 7 there are a couple of changes (compared to CO/RHEL 6). One of it is the use of grub2 instead of grub. Per default the OS seems to use a UUID to "find" the boot-device. Is there an easy to use receipe to get back to device-names…
Nils
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dracut: Switching root

After my hosting company did some changes (no technical description for them) I got the following boot error for my CentOS: What I must do to get my servers up! I tried to ask for support at the hosting company but...
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WDS + GRUB2 UEFI: most menu items not working

We are using WDS to deploy operating systems to several types of machines. As per this small guide, I got the UEFI clients to boot grub, but most of the menu items aren't working. When highlighting a selection and pressing enter, nothing happens,…
kazaamjt
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