whatis init-system
Init System
Also known as: PID 1, init
The first user-space process (PID 1) started by the kernel, responsible for booting the rest of the system and supervising services.
What Is an Init System in Linux?
After the kernel and initramfs finish, the kernel runs /sbin/init. Whatever that is becomes PID 1: it mounts filesystems, starts services, reaps orphaned processes, and handles shutdown.
systemd is the init system on nearly every major distribution. Alternatives like OpenRC, runit, and s6 are used by Alpine, Void, Gentoo, Artix, and some container images.
Example
ps -p 1 -o comm=
# systemdLearn more about Init System
- What Is systemd? systemd is the init system and service manager used by most major Linux distributions. Understanding what it does, how it is structured, and why it replaced older init systems explains a lot about how modern Linux works.
- Process Supervisors: s6, runit, and supervisord Why you might want a supervisor that is not systemd, how each handles the zombie reaping problem in containers, and where each one fits.
- Linux Boot Process Explained From pressing the power button to a login prompt, a Linux system goes through a precise sequence of steps. Understanding each stage -- firmware, bootloader, kernel, initrd, and systemd -- demystifies boot failures and makes the system less of a black box.