Unix and Linux Stack Exchange
Unix and Linux Stack Exchange

Questions tagged [initramfs]

The "initial RAM file system" is the successor of initrd. It is a root filesystem that is embedded into the kernel and loaded early in the boot process.

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Possible missing firmware /lib/firmware/i915/* for module i915

I am getting these warnings every time I update my initramfs image(-s) with update-initramfs on my Dell PowerEdge T20 server running GNU/Linux Debian Buster 10.0. Is there a fix? W: Possible missing firmware /lib/firmware/i915/bxt_dmc_ver1_07.bin…
Vlastimil Burián
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When would you use pivot_root over switch_root?

I'm wanting to understand the Linux init process better in order to netboot a system over ceph rather than nfs. In the process I've come across two forms of switching root. One called switch_root, and the other called pivot_root. These scripts…
hookenz
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Mount root filesystem from initramfs

It's a common scenario. For whatever reason, the initramfs (OpenSUSE, in case it matters) has failed to find the root filesystem, so it drops you into a rescue shell. I know perfectly well what device needs to be mounted though. My question: What is…
MathematicalOrchid
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How to fix boot into initramfs prompt and "mount: can't read '/etc/fstab': No such file or directory" and "No init found"?

Installing a new system using a GPT partitioned disk dedicated to a single partition, ext4 formatted, extlinux (version 4.05) as bootloader, Ubuntu Core version 13.10 amd64 as rootfs, and Ubuntu linux-image-3.11.0-18-generic as kernel, and…
Pro Backup
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Why do I need initramfs?

I found out that if I choose jffs or sd as filesystem (and not initramfs), the kernel size will be very small (1.4 MB as compared to with initramfs which is 3.4MB). It means that initramfs takes considerably large space. So if I can, I'd completely…
gpuguy
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Does initramfs use /etc/fstab?

The way I understand it, initramfs is responsible for loading the "real" root filesystem. Now, there are two places where we define that root. First we put an entry in /etc/fstab. Second, we put the device on the kernel boot commands e.g.…
Ahmed Ghonim
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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 debian and how do I rebuild the initrd.img once…
ChiseledAbs
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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 says The boot loader, such as GRUB, identifies the…
user1028270
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Unlock LUKS encrypted Debian root with key file on boot partition

I'm trying to decrypt the Debian root with a key file stored in the boot partition (decrypted partition). This will break the security, but it doesn't matter now. I have to conclude this successfully or die trying. I have created the hooks to the…
Fusgyus
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Why use cpio for initramfs?

I am making my own initramfs following the Gentoo wiki. Instead of the familiar tar and gzip, the page is telling me to use cpio and gzip. Wikipedia says that cpio is used by the 2.6 kernel's initramfs, but does not explain why. Is this just a…
phunehehe
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extract Embedded initramfs

I have a kernel in which one initramfs is embedded. I want to extract it. I got the output x86 boot sector when I do file bzImage I have System.map file for this kernel image. Is there any way to extract the embedded initramfs image from this…
SHW
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"cryptsetup: ERROR: Couldn't resolve device" combined with "cryptsetup: WARNING: target 'sda3_crypt' not found in /etc/crypttab"

After setting up hibernation on ubuntu 20.04 and modifying it that it works for encrypted swap partitions, I'm getting several issues: First, after rebooting from hibernation, I got "Gave up waiting for suspend/resume device" along with "Volume…
Andreas L.
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How to assemble a specific RAID array without using /etc/mdadm.conf

Is it possible to assemble a specific RAID array using mdadm and its scan-functionality, but without the need for a configuration file? Background: I'm using a custom-made initramfs to setup my system (dm-crypt and other stuff). Everything is done…
maxxim
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How can I force a Ubuntu kernel to fail mounting / and drop into the initramfs rescue shell?

I am trying to customize the initramfs rescue environment and would like to force the kernel to fail mounting / and drop into the (initramfs) rescue shell, as opposed to single user mode. How can I do that? NB: I know how to hook into…
0xC0000022L
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Why does initramfs mount the root filesystem read-only

What is the reason for the root filesystem being mounted ro in the initramfs (and in initrd). For example the Gentoo initramfs guide mounts the root filesystem with: mount -o ro /dev/sda1 /mnt/root Why not the following? mount -o rw /dev/sda1…
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