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Can you unmount the root filesystem?
Normally you cannot just unmount the real root filesystem; if you could do that, you would end up with a situation where you have no way to open any files (and no existing files open, because having any files open in the old root filesystem would prevent its unmounting).
Why is initrd needed?
initrd provides the capability to load a RAM disk by the boot loader. This RAM disk can then be mounted as the root file system and programs can be run from it. Afterwards, a new root file system can be mounted from a different device.
Where is initramfs mounted?
When your root device depends on a module (i.e not compiled in the kernel), such a module _must_ be in the initramfs for your root device to be discovered at boot time. Modules are generally installed at /lib/modules// when you install a kernel package.
How do I unmount Tmpfs?
1 Answer. If you want to permanently remove that, you can just edit /etc/fstab and remove the offending line. But i think that you might be asking for something different. If you want to remove that partition temporarily (until next reboot or remount) you can try sudo umount /tmp .
What is Rootfs Android?
In an Android 9 system-as-root configuration, BOARD_BUILD_SYSTEM_ROOT_IMAGE is set to true , which forces the build to merge the root file system into system. img then mount system. img as the root file system (rootfs). img ; this config is the default behavior for all devices running Android 10.
What is the purpose of Vmlinuz?
vmlinuz is the name of the Linux kernel executable. vmlinuz is a compressed Linux kernel, and it is capable of loading the operating system into memory so that the computer becomes usable and application programs can be run.
Is initramfs required?
For many users, an initramfs system is of no concern. Their system uses a simple partitioning schema with no exotic drivers or setups (like encrypted file systems), so the Linux kernel is entirely capable of handing over control to the init binary on their system. But for many systems, an initramfs is mandatory.
How does the initramfs Mount the root filesystem?
The initramfs will then mount the root filesystem and continue to boot as usual. After the system has booted, you should then repair the underlying issue, for example by running update-initramfs -u. I haven’t yet found a way to tell the initramfs to boot a different device than what /proc/cmdline says. Maybe someone else has an idea?
How to run program other than init out of initramfs?
The kernel command line option “rdinit” tells the kernel to run a program other than /init out of initramfs. For example, “rdinit=/bin/sh” runs a command shell if you have one in there. If your initramfs isn’t doing what you expect, try running a command shell to see what’s up.
How to switch to a different root filesystem?
A common use of initramfs is to find and mount another root filesystem. Since rootfs can’t be unmounted, the way to switch to a different root filesystem is with switch_root command.
Do you need to regenerate the initramfs file system?
It depends on the kind of problem, if the problem was borking the initramfs image itself then you’ll need to actually regenerate it (run update-initramfs) to fix things. Remember the initramfs file system is a RAM filesystem, so to fix anything you need to fix the compressed initramfs image and/or fix the root filesystem.
https://www.youtube.com/watch?v=S6PKNseQS5A