Questions tagged [initrd]

In computing, initrd (initial ramdisk) is a scheme for loading a temporary root file system into memory, which may be used as part of the Linux startup process. initrd and initramfs refer to two different methods of achieving this. Both are commonly used to make preparations before the real root file system can be mounted. Use this tag with questions concerning initrd on Ubuntu.

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Boot loop device as root file system

I created an ext4-filesystem on a loop device with all necessary files to boot with, e.g.: /bin /boot /dev /lib /mnt /etc ... Now I want to boot from the loop device as an image (let's say ...
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Deleted initrd.img and vmlinuz

Running Ubuntu 22.04 LTS and I accidentally deleted initrd.img of ONE kernel and vmlinuz of the OTHER kernel. I can not boot the OS up, not even in recovery mode. How do I restore either initrd.img or ...
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Ubuntu Desktop boots as terminal after replacing missing initrd/initramfs

I updated to 22.04. Had lots of issues but managed to resolve them. Then suddenly while I'm working on an essay, it freezes and I reboot to find that my pc continually freezes during the canonical ...
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How to use d-i and preseeding on 22.04 to automate installations

I am trying to set up an automated installation environment for ubuntu 22.04. We have this already working in production for 20.04 and previous LTS releases for many years. We use pxe/isolinux and a ...
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How to configure Ubuntu automatic updates to house kernel and initrd on EFI ESP

I want to install Ubuntu to an SD-Card integrated into my laptop. My BIOS doesn't expose the SD to UEFI, but I know that it becomes visible to the kernel once it is bootstrapped. Since I have a 1 GB ...
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How do I completely uninstall and reinstall a Linux kernel update?

This problem started when I was installing Ubuntu updates today, 125 packages were to be updated. I ran sudo apt update followed by apt list --upgradable and sudo apt upgrade on my laptop, then ...
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Initramfs-tools script for mounting compressed folders on tmpfs

I'm trying to create a small rescue partition (~800MB spare space after all other system and storage partitions) for a laptop with specialized hardware that requires special kernel and kernel modules ...
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Upgrade 20.10 to 21.04 - hangs on ramdisk

I Upgrade 20.10 to 21.04 from a running system. The upgrade seemed to go OK. It complained about PHP's config file -- This was reasonable since I had made some changes. Etc. Finally, it rebooted, ...
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how can I make the files in initrd visible after casper mount?

after casper mount the entire / gets replaced, thus the files generated by /init or other scripts in initrd will disappear. How can I make those file visible after logging into live system? I can edit ...
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Is it possible to add driver from 5.10 to a older kernel 5.4?

If I have a 5.4 kernel and its initrd, is it enough to copy the desired driver (.ko-file) from 5.10 initrd? If not, why? Does the 5.10 kernel (vmlinuz) have built-in drivers in that does not exist in ...
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How to compile driver module for older kernel?

If my local system is running version 4.4.0-88 and I want to boot a remote system using the 4.4.0-42 kernel with a driver that is only available from 4.14. How to do this? Is it possible? I really ...
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initrd.img doesn't point to the newly (and newer) installed kernel

I'm on Ubuntu 20.04. I was on 5.8.16-050816-generic, this kernel version was installed by downloading from Ubuntu's mainline. Just recently, I manually build kernel 5.14.0-next-20210913+ grabbed from ...
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Kernel build and initrd build

I have a question related to building kernel and initrd. I am following https://wiki.ubuntu.com/Kernel/BuildYourOwnKernel for the kernel build. Will a kernel build involve building initrd as well or ...
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Issue with initrd compression

initrd compression enabled on config file, but kernel images are not compressed. hkk@hkk-NUC7CJYH:~$ grep COMPRESS /etc/initramfs-tools/initramfs.conf COMPRESS=gzip hkk@hkk-NUC7CJYH:/boot$ file ...
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pxe boot ubuntu 20.04 iso to laptops connected with usb-c ethernet cables

So basically i have FOG setup to currently boot windows mdt isos. Ive been working the last few months via trial and error to get this working for Ubuntu. Ubuntu fully works properly via vmware ...
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Ubuntu 20.04 / 21.04 stuck in grub after encryption

SOLUTION: The problem originates from large initrd.img files (~100MB) generated with MODULES=most that can't be loaded due to size limitations. This can be solved by switching to MODULES=dep which ...
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can not get rid of an old initrd.img

I can get rid of initrd.img-3.13.0-100-generic here are my trouble shooting steps user@server:~$ sudo apt purge linux-image-3.13.0-100-generic Reading package lists... Done Building dependency tree ...
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How to use persistent and two(at least) casper-rw partitions on the same computer?

I have a question about GRUB2,Ubuntu and initrd: I need at kernel level(initrd) unknown for me command (with used grub2) to disable boot/detect/use specific partition of disk(by /dev/sdX# or by Label ...
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Hang on black screen after grub

Installed Ubuntu 20.04. I can get into grub by holding down the Esc key. After proceeding to boot the screen goes black (with the backlight on) and nothing more happens. Adding some echo to the grub ...
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Ubuntu 20.04 with ZFS root fails to boot after installing xen

I did some Google searches but failed to find anything for this problem. After installing 20.04 using the ZFS root option I installed Xen. When it rebooted it failed in initramfs with the error "...
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After upgrade to 20.04: luks doesn't open my disk on boot; cryptroot/crypttab is empty, cryptsetup doesn't recognize the crypttab entry

after upgrading to 20.04, my encrypted disk doesn't get decrypted on boot. I'm not asked for any password, so it obviously can't find any partition and boots into initrd prompt. What might be the ...
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install grub on mounted filesystem

I have booted rescue linux (init ram fs), and mounted /dev/sda1 on /mnt/sda1 /dev/sda1 is a linux partition, but /dev/sda has no mbr. How can I install grub on mounted filesystem /mnt/sda1 ? I tried: ...
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Why can't I extract _all_ of the ubuntu-20.04-live-server-amd64.iso initrd?

I can download the server live CD: $ wget http://releases.ubuntu.com/20.04/ubuntu-20.04-live-server-amd64.iso I can extract its contents: $ 7z x -aoa -o./ubuntu-20.04-live-server-amd64.iso.d ubuntu-...
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Unpacking .lz format: what does this command do?

I'm trying to unpack Ubuntu Desktop's initial ramdisk (initrd.lz) to inspect some casper components. The lz format is indeed interesting, but what more surprises me is the unpacking method (that ...
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Ubuntu 20.04 long unpacking rootfs

i changed plymouth in Ubuntu 20.04 as here: Ubuntu 20.04 logo checking disk live ISO After recompile initrd by this code my initrd has 48MB (oryginal has 82MB). New, recompiled initrd is smaller but ...
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How many initrd.img files should I have on my linux server?

I have a server I'm maintaining, and on weekly bases, I basically have to delete some big files like old backups and what not to keep the server from crashing and reaching maximum capacity. Although ...
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How to extract initrd from ubuntu-20.04-live-server-amd64.iso

I am trying to update a process used to remaster the Ubuntu 18.04 install image for 20.04 and running into a problem with extracting the initrd archive. The command used is cpio -id --no-absolute-...
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Boot partition keeps filling up with old inird.img files

Here are the contents of /boot: drwxr-xr-x 5 root root 3072 Apr 18 09:10 . drwxr-xr-x 26 root root 4096 Mar 22 15:43 .. -rw-r--r-- 1 root root 217495 Jan 17 05:59 config-4.15.0-76-generic ...
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18.04 grub freezes when reaching initrd on first boot

Happens ALWAYS, just after I turn on the desktop pc, and only once. Then I have to soft reboot (ctrl+alt+del) (instead of use the desktop reset button). After that soft reboot, it boots normally. ...
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Anyone have a writeup for recovering 19,10 ZFS pool correctly -- stuck in initrd

I did the root zfs install and everything worked great. After shutting down I was unable to reboot and got stuck at initrd shell prompt. Reinstalled from scratch on same SSD. Rebooted. Worked great....
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Maas ubuntu 18.04 initrd boot loop

I have strange situation, maas won't boot my servers with 18.04 ubuntu, but if I repack initrd from gzip to lzma - it starts working. I had to change boot-resource "current" symlink to directory and ...
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Extracting all files from a initrd cpio archive. How Do I?

I have a initrd that i would like to extract the contents of. lsinitramfs displays a few directories including kernel, var, lib, usr. But when i cat initrd.img | cpio -id, only the kernel directory ...
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Automated PXE boot image selection and customized boot images

Details I have a network of about 20 identical Dell PCs and 40 raspberry PI 3b+ units which were donated to a school where I'm currently doing some pro-bono work. The RPI units are for kids to browse ...
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Is there a single init script in Ubuntu 16.04 for the invocation of the booting or separate directories?

If so, where are they located? And can the init script be modified according to the system requirements? I located the /etc/init folder and I wanted to know, since Suse has one init script, does ...
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Why did the Kernel unpacking failed?

The kernel on booting initrd, shows the error 'Initramfs unpacking failed: junk in compressed archive', with a message of kernel panic. Is this an issue with cpio, as I'm using Ubuntu 16.04 or some ...
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lsinitrd shows no module in 18.04.1

In my experience in CentOS7, just type lsinitrd I can get modules in initrd, but in Ubuntu 18, I need to type lsinitd /boot/initrd.img-4.xxxx-generic However, it still show nothing about module.
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How to modify initrd initial ramdisk of Ubuntu 18.10 Cosmic Cuttlefish

I tried to extract the initrd casper/initrd of Ubuntu 18.10 and got an unexpected result. I did not see the root filesystem and files, but just a folder named kernel. What I have done Firstly I ...
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How can I add a command to initramfs / initrd to execute before mounting the root partition?

ubuntu 18.04 64-bit I have a setup which has three separate block crypt devices, plus a non-encrypted /boot. If I had started with a clean sheet of paper, I could have done it with two, but it would ...
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preseed.cfg installed in initrd root not being recognized in Ubuntu installation (17.10 amd64 desktop or server)

I have been using a process for preseeding the initrd in a Debian ISO for some time. I just tried the same process for desktop and server variants of Ubuntu 17.10 ISOs, and everything looks fine until ...
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How to use cryptsetup keyscript with initrd in Ubuntu 16.04?

I am setting up an encrypted partition with a special script to automatically input the passphrase. The partition is not a system partition and the process requires a custom keyscript. I've managed ...
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/sbin/init : no such file or directory | Not able to boot ubuntu desktop

I have been using Ubuntu Desktop for a while now, but today for some reason I am not able to start it. Here is what I see. Here is what I have already tried : Tried booting in recovery mode ...
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How to load a ramdisk now?

latest kernels have made ramdisk modules: CONFIG_BLK_DEV_RAM=m Which is the module and where to find it. Is loadable during boot from initramfs ? I had root on software RAID1 with SSD and Ramdisk (...
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What is the relationship between initrd and squashfs?

If we are using initrd for, say in live usb, why would we also need squashfs?
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