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.
166
questions
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Headless Ubuntu server machine sometimes stuck at GRUB menu
I have Ubuntu 10.10 Server installed on a single-board machine in a semi-embedded environment; no keyboard or screen, just SSH access to it.
So it's really frustrating when it occasionally boots up ...
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GRUB "Some modules may be missing from core image" warning
one HDD crashed from my RAID and I added a new HDD.
Now I wanted to install GRUB to the new HDD: with grub-install /dev/sdb.
I get these warnings:
Installing for i386-pc platform.
grub-install: ...
11
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3
answers
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How to install grub on multiple disks?
I have weird situation - order of disks as reported by BIOS, is different than order of disks that Linux sees.
Which makes for problematic run - grub installs to sda, but bios boots from sdd or ...
9
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1
answer
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How to force Debian to boot new Kernel?
I'm running Debian 6, Debian GNU/Linux, with Linux 2.6.32-5-amd64 under Grub2 ( 1.98+20100804-14+squeeze1) on a remote system (no possibility to view the pre-boot messages). I compiled and installed a ...
9
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1
answer
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Ubuntu server, gpt partition table, mdadm, grub boot fail
Basic working system details:
I used the Ubuntu 12.04 server CD to install a server.
I have 4 disks. On all disks I did the following, similar to this howto :
created a 2GB swap partition
created a ...
8
votes
2
answers
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Grub2 reports physical volume pv0 not found on server non bootable anymore
I first installed my ubuntu server (11.10 amd64) using lvm but not fully mastering the concept of it. I think that's partly what made the mess of partitions on my two disks (seems to me). I installed ...
7
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1
answer
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How can I find out where GRUB was installed?
I need to find where GRUB was installed, for example, which drive/partition. Is it possible to figure out where it was installed?
7
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4
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Linux Software RAID1: How to boot after (physically) removing /dev/sda? (LVM, mdadm, Grub2)
A server set up with Debian 6.0/squeeze. During the squeeze installation, I configured the two 500GB SATA disks (/dev/sda and /dev/sdb) as a RAID1 (managed with mdadm). The RAID keeps a 500 GB LVM ...
7
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1
answer
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How Do You Non-Destructively Check if grub2 is Installed in The Boot Sector or is Being Chain-Loaded by grub1, Without Rebooting?
We're upgrading several systems from Debian Lenny to Squeeze and I'd like to ensure that I haven't missed any grub2 installations. By default, Squeeze chain-boot-loads from grub1 and you have to run ...
7
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3
answers
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GRUB hangs before menu, after a HDD upgrade. How to debug?
I have a problem on a server with 4 x 1 TB drives running Debian wheezy and
GRUB 1.99-27+deb7u3.
sda and sdb have partitions mirrored using (Linux software) RAID1, including /boot. sdc and sdd have a ...
6
votes
2
answers
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Grub rescue, will not boot from mdadm RAID, no such disk or device -- mduuid wrong?
I am running a 14 disk RAID 6 on mdadm behind 2 LSI SAS2008's in JBOD mode (no HW raid) on Debian 7 in BIOS legacy mode.
Grub2 is dropping to a rescue shell complaining that "no such device" exists ...
6
votes
1
answer
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CentOS 7: GPT and software RAID 1 without 'biosboot' partition
I have a CentOS 6 server with software RAID1 (2x3TB):
- sda
# parted /dev/sda unit s print
Model: ATA TOSHIBA DT01ACA3 (scsi)
Disk /dev/sda: 5860533168s
Sector size (logical/physical): 512B/4096B
...
5
votes
2
answers
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Setting up Linux softRAID10 so it can boot after a drive failure
I would like my RAID10 to survive the failure of the bootdisk. I want to write grub to the MBR of each disk in the array so that in the case of a failure the array will still boot on the remaining ...
4
votes
2
answers
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How do I add xen kernel boot parameters in grub2?
I know that I can add command line parameters to the grub2 command line by editing
/etc/default/grub according to this answer
How do I add a boot parameter to grub2 in Ubuntu 10.10?
However, that ...
4
votes
2
answers
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Debian 12 (bookworm): Installing a software RAID 1 fails with grub error
For a while I have been trying to set up a new server system with a RAID 1 as boot source. That RAID consists of two 4TB Harddisks. So I boot from an USB stick that I have prepared with the ...
4
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1
answer
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GRUB_DEFAULT seems to be ineffectual when trying to boot a custom kernel by ID on Debian 8
I've built a custom kernel on a Debian 8 machine, and I want to set it as the default. A seemingly simple task, but I can't get it to work for the life of me.
I built my kernel using the official ...
4
votes
2
answers
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update grub2 without hardware access (e.g. in a chroot)?
I'm writing a script that takes a master KVM image, converts it to VDI, makes a few changes to it,
and offers it up for download.
I need to update the kernel boot parameters for some of the newly ...
4
votes
1
answer
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Grub2 reports physical volume pv0 not found when probing/installing
I upgraded a Ubuntu Maverick to Precise server but I get the following error while updating grub:
error: physical volume pv0 not found.
Now, for my system I have /dev/sda through /dev/sde
/dev/sda1 ...
4
votes
1
answer
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kickstart over HTTPS only
Background: Kickstarting RHEL7 on powerppc (IBM pSeries)
So I've kickstarted unattended for years, and had to use yaboot, NFS, etc. for kickstart in the past. Trying to modernize now. I have a ...
3
votes
2
answers
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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-...
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votes
3
answers
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RAID6 mdraid -> LVM -> EXT4 root with GRUB2?
2012-03-31 Debian Wheezy daily build in VirtualBox 4.1.2, 6 disk devices.
My steps to reproduce so far:
Setup one partition, using the entire disk, as a physical volume for RAID, per disk
Setup a ...
3
votes
2
answers
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how to disable serial console after successful boot (systemd/grub2)
I enable the serial console during the boot process on centos7 which uses grub2 and systemd (instead of inittab)
I would like to undo that serial input/output at the very end of the boot, after a ...
3
votes
1
answer
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Setup grub2 on a GPT software raid 3 TB HDD
I like to setup grub2 on a GPT softare raid 3 TB HDD.
Number Start (sector) End (sector) Size Code Name
1 2048 1050623 512.0 MiB FD00 Linux RAID
2 ...
3
votes
1
answer
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Install debian 8 on a LVM Volume with Type RAID1 GRUB2 cant find volume group
Hello Community!
I tried the whole day long to setup up an LVM type Raid1
Volume on Debian 8.5, but the Server is not be able to
boot from it.
First of all here is the error i get from GRUB2:
...
3
votes
2
answers
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views
How to boot GRUB2 so it mounts "root" on a different drive (remote server without KVM switch)
Summary:
I created a copy of the root file system on a RAID array (with one disk on it), I tried to get the system to boot off that newly copied drive.
Background:
2 disks of the same size in ...
3
votes
3
answers
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Getting Grub2 to recognize a Raid 10 boot/root
I've been trying to get my raid to boot from grub2 for about 2 days now and I don't seem to be getting closer. The problem appears to be that it doesn't recognize my raid at all. It doesn't see (md0) ...
3
votes
1
answer
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Package upgrade on Ubuntu raid server and grub setup issue
I have remote Ubuntu 10.10 server running on raid system. I did package upgrade yesterday night for security reasons. During the upgrade, grub installation screen appeared and asked me which partition ...
3
votes
0
answers
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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 ...
3
votes
0
answers
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Booting a squashed filesystem from ISO
I am trying to create a UEFI bootable CD ISO with a squashed filesystem from a virtual machine, which I provisioned with the stuff I need.
To explain:
I use packer and a kickstart file to install ...
3
votes
0
answers
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EC2 AMI instance store backup grub utility required
Working on backup of whole ec2 volume and image to upload to s3. Using RHEL7 and it internally uses Grub2 as bootloader. EC2 AMI tools requires grub legacy loader and I'm struck up in this loader. ...
3
votes
1
answer
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How do I use memtest86+'s "badram" output with GRUB2? [closed]
So after a while of things randomly crashing, I let memtest86+ run overnight, and it found errors.
I enabled the "badram" error output, but every few seconds it shows me a differing selection of ...
2
votes
2
answers
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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 ...
2
votes
2
answers
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I deleted all the contents of /boot and now server is not booting
I did something stupid. My thinking was that /boot directory is empty and contents come to /boot each time the computer starts. My /boot drive was giving me error messages no space left so I thought ...
2
votes
1
answer
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Can't get rid of mystery kernel
Just noticed that despite having the kernel updated regularly, the version in use is quite outdated:
$ uname -a
Linux test 2.6.31-302-rs #7 SMP Thu Oct 29 22:57:03 UTC 2009 x86_64 x86_64 x86_64 GNU/...
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1
answer
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In CentOS 7, is there a way to specify which block devices should be tuned with the scheduler (or ELEVATOR)?
In CentOS 6, there was /etc/tune-profiles/my-server/ktune.sysconfig with this text(I'm referring to the comments that explain what the code is doing):
# This is the I/O scheduler ktune will use. ...
2
votes
2
answers
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XenServer 6.2 VM 100% CPU and 100% memory usage and won't boot
I had this problem today after a power failure.
I had 2 vms and one of them won't boot and was using 100% of CPU and 100% of memory.
Since it was very dificult to solve (at least for me) I want to ...
2
votes
1
answer
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Why does my server not boot after moving root fs, inside LVM, to raid?
I'm trying to move my root partition to raid based physical volumes, and
I seem to be failing.
The procedure I'm using is somewhat complicated, but that's because my
hosting provider has very limited ...
2
votes
1
answer
9k
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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 ...
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votes
2
answers
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Grub incorrectly escapes $ character in its settings
Not sure where I make mistake but I can't escape $ correctly in /etc/default/grub. I'm on Ubuntu MATE 18.04. This is what I do:
In console I edit confid by calling
sudo mcedit /etc/default/grub
I ...
2
votes
1
answer
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How to fix "Setting up grub-pc" freezing during apt-get upgrade?
I have a packer script that builds up a virtual image using Ubuntu. The script today started getting stuck during apt-get dist-upgrade on amazon-ebs: Setting up grub-pc.
I found many people on the ...
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votes
2
answers
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Restore GRUB2 after Clonezilla
After restore from clonezilla backup, grub2 is broken.
I see "GNU GRUB minimal BASH-like line editing is supported.."..
I have one HDD, with two partition (/boot , and /)
default settings
How do I ...
2
votes
2
answers
3k
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Centos grub bootloader missing after installing windows 10 [closed]
I first installed CentOS 7 on my laptop, 2nd I installed Windows 10 in same hard disk with different partition, but I couldn't get my Centos 7 info in windows boot loader. I tried easyBCD tool to get ...
2
votes
1
answer
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Setting bootloader password in EL7
Using this guide I am attempting to add a bootloader password to a CentOS7 install.
When prompted, enter the password that was selected and insert the
returned password hash into the appropriate ...
2
votes
3
answers
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Ubuntu/Grub2: Crypted grub password doesn't work, what could be the reason?
I've used the command grub-mkpasswd-pbkdf2 in order to encrypt my password, then I took the hashed password and placed it in my Ubuntu 14.04 /etc/grub.d/00_header:
cat << EOF
set superusers="...
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votes
3
answers
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Ubuntu Grub fails with: unknown command recordfail
I installed some patches on a Ubuntu 10.04 Server (LTS) system today. After rebooting the newly patched server the boot process is now hosed with an unknown command 'recordfail' message.
If I hit a ...
2
votes
1
answer
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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 ...
2
votes
1
answer
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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.
...
2
votes
0
answers
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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 (...
2
votes
1
answer
276
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Are my EFI partitions mutually bootable? How to interpret the output of efibootmgr -v
I have two GPT formatted disks both starting with EFI partitions and followed by a single physical raid partition. I installed ubuntu-server 16.04 with software raid over these two raid partitions and ...
2
votes
0
answers
693
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Can't find (inactive?) LVM (with root FS) on boot
I'm running a Linux Server using ArchLinux, mostly for my own development needs.
It runs Arch Linux on a SW-RAID1.
There's two disk drives sda and sdb, each with 3 partitions sda1-sda3, sdb1-3.
SDA1+...