How to boot from the initrd file system?
The initrd file system is then unmounted, or, if it is still busy, moved to a directory /initrd, if such a directory exists on the new root file system. In order to use this mechanism, you do not have to specify the boot command options root, init]
Can a root file system be mounted from a different device?
Afterwards, a new root file system can be mounted from a different device. The previous root (from initrd) is then moved to a directory and can be subsequently unmounted.
What happens to the previous root in initrd?
The previous root (from initrd) is then moved to a directory and can be subsequently unmounted. initrd is mainly designed to allow system startup to occur in two phases, where the kernel comes up with a minimum set of compiled-in drivers, and where additional modules are loaded from initrd.
Can you change the root directory on initrd?
Note that changing the root directory does not involve unmounting it. It is therefore possible to leave processes running on initrd during that procedure. Also note that file systems mounted under initrd continue to be accessible.
How is the initial RAM disk ( initrd ) used?
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. The previous root (from initrd) is then moved to a directory and can be subsequently unmounted.
Can you boot using initrd and rootfs AD root?
I try to boot system using initrd and rootfs ad root=/dev/ram0. I need separate kernel and filesystem images. All related kernel options was set properly (suppose). Command line arguments passed. May be I miss something? Look on the web and that forum, compare my settings and don’t understand where errors? Is this mode supported on BF or not?
How to Mount rootfs using initrd and / Dev / RAM0?
Kernel command line: root=/dev/ram0 rw initrd=400000,8M ramdisk_size=8192 ip=dhcp waitroot earlyprintk=serial,uart0,57600 console=ttyBF0,57600 U-Boot 2015.07 ADI-2014R1-pre-00454-gfabdc61-dirty (Aug 09 2016 – 22:46:31 +0300)
What happens if rootfs does not contain an init program?
If rootfs does not contain an init program after the embedded cpio archive is extracted into it, the kernel will fall through to the older code to locate and mount a root partition, then exec some variant of /sbin/init out of that. All this differs from the old initrd in several ways:
Where does the initrd go in the Linux kernel?
This is of course limited to initrds that do not interfere with the general system state (e.g. by reconfiguring network interfaces, overwriting mounted devices, trying to start already running demons, etc. Note however that it is usually possible to use pivot_root in such a chroot’ed initrd environment.) the initrd is now in the file “initrd”.