Unix and Linux Stack Exchange
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Questions tagged [root-filesystem]

The root filesystem (`/`) contains the kernel and utilities needed to boot a system.

The root filesystem is the filesystem containing the root directory /. Other filesystems can subsequently be attached as subtrees of this. The program is loaded from the root filesystem and may kickstarts a process to mount other filesystems.

Traditionally the root filesystem is the first to be mounted. On Linux, it is common to first mount another filesystem from an image in memory, either or . This initial filesystem contains additional software which may be needed to access the root filesystem, for example if the device containing the root filesystem requires additional drivers, or if the root filesystem is encrypted and the user must enter a passphrase to decrypt it. Once the root filesystem is accessible, it is mounted and the normal boot process starts with .

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Change permisions of a file with my cat's help

root@system:~# less myfile -bash: /bin/less: Input/output error The root filesystem is dead. But my cat is still alive (in my memory): root@system:~# cat > /tmp/somefile C^d root@system:~# He's kind of lonely though, all his friends are…
loopbackbee
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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…
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How is /etc/fstab accessed before root is mounted?

I was making some changes to /etc/fstab, when this chicken and egg question occurred to me - if /etc/fstab contains the instructions for mounting the file systems, including the root partition, then how does the OS read that file in the first place?
sashoalm
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What are the minimum root filesystem applications that are required to fully boot linux?

It's a question about user space applications, but hear me out! Three "applications", so to speak, are required to boot a functional distribution of Linux: Bootloader - For embedded typically that's U-Boot, although not a hard requirement. Kernel -…
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Is using a read only root file system a good idea for embedded setup?

I have been tasked with running Linux as an operating system on an embedded device. The target has an x86 processor and has 8 GB CompactFlash device for storage. I have managed to use buildroot to create the kernel image and cross compilation…
mathematician1975
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Does POSIX limit the number of directories in the os root?

I'm trying to learn the POSIX standard. When using Unix, I have /bin, /etc, /dev, /media, and usually /opt, but is that standardized or up to your spec implementation? Could there be many directories in the root, or is it limited by the standard?
Niklas Rosencrantz
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Why on some Linux systems, does the root filesystem appear as /dev/root instead of /dev/in mtab?

I've seen on various Linux systems where instead of the real device node (for example: /dev/sda1), the root device appears as /dev/root, or instead of the real filesystem, mtab says it is a filesystem called rootfs (which appears as a real…
Billy
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Can virtfs/9p be used as root file system?

Is it possible to use a folder shared from the host to the guest via virtfs/9p as the root file system inside the guest? Loosely related to my previous question: Can virtfs/9p be used to share the same host folder with multiple guests?
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What is zImage, rootfs

I am very much new to Embedded Linux. We use poky build system. We just use bitbake linux-imx command to build the kernel. It generates some files zImage, rootfs, uboot and also a sdcard image. We just copy the sdcard image and run the linux on our…
seereddi sekhar
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Any reason for encrypted /?

I am a big fan of linux and like trying out new distros now and then. I usually have my home folders and roots in a lvm atop an encrypted partition, but this tends to become cumbersome with every initramfs creation process being more alien than the…
nikitautiu
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Unable to find root device ''

ERROR: device '' not found. Skipping fsck. ERROR: Unable to find root device ''. You are being dropped to recovery shell I've been trying to install Arch Linux for some time, and keep running into this error. I seriously have no idea what to do. A…
TheInitializer
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Deleted /tmp accidently

Accidently, I ran sudo rm -r /tmp, is that a problem ? I recreated it using sudo mkdir /tmp, does that fix the problem ? After I recreated the directory, In the places section in the sidebar in nautilus in Ubuntu 14.04 I can see /tmp , which wasn't…
Amr Ayman
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Running QEMU with a root file system directory instead of disk image

In order to test the root file system i need to run QEMU with created disk image as root file system, the QEMU accepts -kernel which can be used for specifying kernel directly without deploying it inside root file system, however i need similar…
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How big should the rootfs partition should be on Arch Linux?

I've installed ArchLinux yesterday and set up a 10 GB partition for the root file system, 256 MB for swap, and the rest (456 GB) for my /home. However I still have 4.0 GB left on my root file system after installing some packages (GNOME, Firefox,…
Ben D
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What is the purpose of listing the rootfs in /etc/fstab?

In BuildRoot 2015.08.1 /etc/fstab contains the following line. /dev/root / ext2 rw,noauto 0 1 On my encrypted Ubuntu laptop /etc/fstab contains the following line. /dev/mapper/ubuntu--vg-root / ext4 errors=remount-ro 0 1 Question: What is the…
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