Questions tagged [initrd]

initrd is a method for loading a temporary file system into memory, during the process of booting the Linux kernel.

Filter by
Sorted by
Tagged with
1
vote
4answers
13k views

How to change the boot kernel of a usb live w/ persistent running Kali

First, the issue that I'm having is being unable to run VirtualBox on Kali 2.0. I set up a usb live with persistence running Kali 2.0, which at the time had the 4.6.0-kali1-amd64 kernel. I have ...
1
vote
1answer
2k views

Can't find initrd file on GRUB console

My PC boots to the grub command line. $ ls (hd0) (hd1) (hd1,gpt6) (hd1,gpt5) (hd1,gpt4) (hd1,gpt3) (hd1,gpt2) (hd1,gpt1) (lvm/fedora-swap) (lvm/fedora-home) (lvm/fedora-root) $ ls (hd1,gpt5)/ ...
2
votes
1answer
2k views

Proper manual OS setup on LUKS encrypted drive with non-aes algorithm on yum-based distro (CentOS)

I'm trying to achieve LUKS-encrypted CentOS 7 install with separate /boot partition and lvm on EFI-friendly motherboard. I've done partitioning fresh CentOS install from old CentOS(installed from GUI)...
7
votes
2answers
1k views

Repack the filesystem image from vmlinux.bin (embedded initramfs) without rebuilding?

In How do I extract the filesystem image from vmlinux.bin? and https://wiki.gentoo.org/wiki/Custom_Initramfs#Salvaging methods are presented for getting and unpacking an embedded initramfs/initrd ...
1
vote
0answers
78 views

Flavour of initrd

This Arch wiki page says: If you are using a systemd based initrd, you must pass: rd.luks.options=discard How do I query the initrd mini-shell to find out if I am running a systemd-based initrd?...
0
votes
1answer
2k views

uCLinux (linux 4.9 nommu) VFS: Cannot open root device “(null)”

I'm stuck with this kernel panic. What I want is to embed an initramfs into the kernel xip Image, but linux panic and tell me to pass a valid "root=" rootfs value. But WHY does Linux look for this ...
2
votes
2answers
1k views

Why don't we include File System drivers in the kernel itself instead of using Initrd/Initramfs

The Linux kernel contains very minimal code that is necessary to boot on a majority of devices but I don't get the point of having Initrd/Initramfs.As far as I've understood Initrd/Initramfs job is to ...
1
vote
1answer
900 views

GRUB freezes after loading initrd unless exact steps are taken

I have a HP Notebook 15-f004wm, which I use as my daily driver. However, there's a strange issue where GRUB "freezes" (a.k.a can't get past "Loading initrd...") whenever I try to boot. The only way ...
2
votes
1answer
2k views

switch_root gives Invalid argument

My goal is to unmount the root disk so I can format it. To do this, I want to switch root from the hard disk to some other root. I have chosen to use the files from the initramfs (which contains a ...
2
votes
2answers
827 views

Initramfs and Block Devices

In this introduction to initramfs, Robert Landley mentions the following as the motivation behind ramfs. But ramdisks actually waste even more memory due to caching. Linux is designed to cache ...
1
vote
1answer
320 views

How to use only automatically build RAID arrays on Ubuntu?

I have an Ubuntu 16.06 system where / on an SSD primary partition and /home with md RAID0 on four SSD devices. The file /etc/mdadm/mdadm.conf is automatically generated by mkconf and contains no ...
1
vote
1answer
3k views

initrd built with NFS module cannot mount NFS root

I'm building a custom initrd so that I can boot diskless nodes with a tmpfs root rather than NFS root (a script in the initrd copies the contents of the root device to a tmpfs filesystem, then changes ...
1
vote
2answers
183 views

Can initramfs programs access all memory - do they run in real or protected mode?

This is in the context of current 64-bit processors and current linux kernels (I'm using 4.6.4.) Is it possible for me to write a program that during boot can examine base memory, 640k and under, ...
1
vote
2answers
2k views

Booting kernel (FIT image) with no rootfs

An embedded Linux device I am working with has the following kernel parameter: root=/dev/ram0 Additionally, the kernel image is bundled together with an initrd and device tree to make a flattened ...
3
votes
1answer
4k views

Patching the kernel to allow booting without initrd

The first answer of 'Why does Linux use an Initial Ram Disk at boot?' states that the initrd/initial ram filesystem is used to provide drivers to mount the real root filesystem. It also says that it ...
0
votes
1answer
98 views

linux + dose each security kernel rpm will install the relevant initrd and vmlinuz files under /boot

I just print the kernel rpms that need to install on my redhat machine (version 6.5) # yum list-security --security | grep kernel-[0-9] RHSA-2014:1143 security kernel-2.6.18-371.12.1.el5.x86_64 ...
5
votes
3answers
4k views

Why do we need initramfs and initrd

For example we have exotic file system on the disk and in order to load system we need mount root filesystem. But we cannot because there is no suitable driver exists in kernel image. Let me ...
1
vote
2answers
698 views

Server stuck at “Loading initial ramdisk” when using NVidia GPU

I have a server with an NVidia M4000 Quaddro card. In my server BIOS, if I set the GPU priority to 'onboard', my system boots and I can use the NVidia card. If I set the GPU priority to 'external', my ...
1
vote
0answers
3k views

Add AHCI to initrd on CentOS7 after installation

I built a complete CentOS7 system with lots of tools, preferences, etc in a VMware guest. Once working fine I moved it to my physical server. I managed to get grub2 installed and the bootloader now ...
1
vote
1answer
919 views

Shell prompt from initrd

I have a problem with a Linux system that won't boot. The bootloader happily loads the kernel and initrd, but then the initrd script whines and complains and moans that it can't find the root device. ...
6
votes
2answers
8k views

How to make a minimal bootable linux (only with terminal) from kernel source code? [duplicate]

I want to make a very minimal linux os which only have a terminal interface and basic commands/applications (busybox is my choice for commands/apps). I don't want the installation option on my os. I ...
18
votes
1answer
27k views

What is the equivalent of mkinitcpio.conf on debian?

I want to review that the hooks used to build the initrd.img are correct in my debian but I fail to find the /etc/mkinitcpio.conf file like the one in Archlinux, what is the equivalent of this file in ...
2
votes
0answers
617 views

Cannot boot kali linux after dist-upgrade, stucks at 'Loading initial ramdisk …'

I did a dist-upgrade from 4.3.0-kali1-amd64 to 4.4.0-kali1-amd64 but when I restart, the screen stucks at 'Loading initial ramdisk ...'. I had to use the advanced boot options to boot using 4.3.0-...
0
votes
1answer
490 views

Running code before initrd has been removed and after the root filesystem has been mounted

I looked here Kernel boot process and I tried to understand how to run a script before initrd filesystem removed and but after the root filesystem has been mounted (EncFS), If I understand it ...
2
votes
2answers
7k views

Debian: Boot fails when mounting sda with “invalid argument”

I am trying to move a Debian squeeze installation to VMWare VSphere 5.5 environment. However when booting the new machine after replication, the initrd/busybox gives an error, that it cannot mount the ...
1
vote
1answer
414 views

LVM devices not showing in initrd but working on boot [duplicate]

I am currently working on a custom initrd based on the CentOS 6.7 (2.6) kernel with the following modules loaded. The initrd is designed to backup files off a old RHEL system into memory, unmount the ...
15
votes
3answers
8k views

Is the entire kernel loaded into memory on boot?

I read through this popular IBM doc (I see it referred quite often on the web) explaining the function of the initial RAM disk. I hit a wall in conceptualizing how this works though. In the doc it ...
1
vote
0answers
123 views

Interaction of initrd commands and systemd services doing same thing

I have a general idea of how the boot process works, but now that I'm customizing the initrd process, I can't wrap my mind around this. If there's a systemd service that can connect to a remote ...
0
votes
1answer
994 views

How to extract initrd image from RHEL iso and put a script in initrd /bin/

I have written a customized shell script(command) ,which i want to put in initrd /bin and then, i want it to be copied to Linux OS /opt/xyz directory .Where xyz is customized directory created during ...
0
votes
0answers
2k views

New Fedora Install Hangs on Initrd Default Target

I am attempting to install Fedora 19 on a brand new system. Here is my HW. Intel Core i5-6500 6M Skylake GIGABYTE G1 Gaming GA-Z170X-Gaming 3 (rev. 1.0) LGA 1151 Intel Z170 HDMI SATA 6Gb/s USB 3.1 ...
3
votes
2answers
1k views

Is there a way to get Linux to treat an initramfs as the final root filesystem?

I want to boot a system with an initramfs that's the actual final filesystem, not a temporary initramfs for loading drivers. Unfortunately, Linux imposes different (and in my case, undesirable) ...
1
vote
2answers
2k views

Are there any tools to edit the initrd file in Windows?

Currently I am running on a Windows machine. I would like to modify a Linux ISO before installing it. For this I need to change a package inside initrd. Is there a way to do this from Windows?
1
vote
0answers
384 views

Mounting real rootfs after initial booting using initrd

I'm booting kernel with root=/dev/ram0 on a embedded environment. After initial booting, how can I mount real rootfs present at /dev/mtd3 and make it as the only rootfs. I'm using root=/dev/ram0 ...
0
votes
1answer
1k views

how to add application to initrd.gz

I have an initrd.gz (from linux parag*n live cd) I want to edit the file inside and add app like apache,ophcrack,etc. So far I've done extracting by following these step wiki.ubuntu.com/...
1
vote
1answer
567 views

initrd.img contains many archives

I'm new here, hope I'm posting in the right section... Well, I got the initrd.img of debian 3.16.0-4-686-pae (downloaded and burned whole iso). If I boot from disk or lan initrd is ok, everything ...
2
votes
1answer
1k views

Change the kernel in downloaded Ubuntu Image [closed]

I'm adding multiple new system calls to kernel. I want to test my custom kernel by making an bootable ISO out of it trying to boot on another machine. As a part of making this bootable ISO, I got ...
2
votes
1answer
743 views

Linux initrd environment setup - Failed to execute /init

I'm looking for help in getting a basic initrd environment up and running. My goal is to enhance my knowledge on how to create a basic Linux environment. Ideally, I would like to move into Embedded ...
40
votes
6answers
15k views

Why is it that my initrd only has one directory, namely, 'kernel'?

I'm using debian live-build to work on a bootable system. By the end of the process i get the typical files used to boot a live system: a squashfs file, some GRUB modules and config files, and an ...
3
votes
1answer
2k views

How can I replace root / filesystem with another filesystem?

When the Linux kernel starts up, it uses initrd as the root / filesystem, then replaces that with a filesystem partition in fstab. Based on a test in an early init script, I want to replace that root ...
0
votes
1answer
1k views

qemu can't run linux kernel

I saw this question and I did pretty much the same but I enabled initrd in configuration to use temporary root file system and no other modification but I still get this error on: qemu -kernel linux-...
2
votes
2answers
970 views

How can I remotely debug a broken initrd?

Background I have a system that runs Linux. It's a NAS, and does not have any monitor, keyboard, or serial port. It does have a network port. I'm not happy with the software running on it, and am ...
1
vote
1answer
538 views

Built new kernel, LVM won't mount from initrd

I need to upgrade my kernel on a RHEL 5 system to build with some experimental drivers. I have configured the kernel with module loading for LVM (dm_* modules). Once the initrd runs the /init ...
5
votes
4answers
12k views

Unpack, modify and pack initrd as a user

I've got a problem with rebuilding the initrd image as a user. Firstly, when I try to "unpack" the original initrd image: cpio -idm < initrd-base cpio: dev/tty8: Cannot mknod: Operation not ...
1
vote
0answers
651 views

Build Mini Linux and Embedded Linux

How to build Mini Linux with Busybox, Kernel-3.15.3, Syslinux? I've built my Mini Linux using these steps: Steps in Building Base Mini Linux Distro 0 . Compile the kernel and see the ...
4
votes
1answer
1k views

Are there any canned solutions for running sshd in the initrd?

This is mostly aimed at Debian/Ubuntu, but I feel savvy enough on a variety of distros to be able to adapt the solution for one distro to another. Here's my scenario. There are a few situations when ...
-3
votes
1answer
293 views

Which would mount faster initrd or initramfs ? [closed]

I want to boot my linux as fast as possible. I have to make a choice between initrd and intiramfs. Which one should mount faster and have smaller size?
2
votes
0answers
2k views

Why do I need to specify two init images - initrd and boot - inside KVM to boot to bash?

My machine is running inside a KVM virtual machine (Parallels Desktop v8), having a BIOS (not UEFI), having one SATA drive connected, one GPT partition on that disk, the partition is ext4 formatted, ...
0
votes
1answer
346 views

How are the services exactly starting in (K)Ubuntu?

I have latest Kubuntu. I have installed mysql. I was looking into the /etc/init. I see the following: In /etc/init/mysql.conf description "MySQL Server" ...
2
votes
1answer
2k views

How to show progress when loading initrd?

I have a complete root fs built into initrd, so it's almost 500MB. It takes a while to load to memory and during this time, the screen has no indication of the progress. I would like to know if there ...
5
votes
1answer
1k views

How do I load initrd into memory to be passed to kernel when using kexec?

As the MIPS port of kexec doesn't support the --initrd param, I'm looking for workarounds to imitate the feature. According to Linux/MIPS wiki, MIPS kernels support rd_start and rd_size kernel command ...