The initialization manager is an important part of the root filesystem. It is the first thing the kernel executes, and it has the responsibility to start the rest of the system, and manages system shutdown too.

The initialization manager is usually fixed by the Linux distribution. The Poky distribution allows you to select between initialization managers, the most used being System V init (sysvinit) and systemd. The poky-tiny distribution has no initialization manager and uses BusyBox init to directly read the inittab file and launch programs.

The UNIX System V operating system introduced an initialization system that was the basis for Linux's initialization. Several recent attempts have been made to replace it, and systemd has finally managed to get enough traction in between Linux distributions to be considered the successor to sysvinit.

This recipe will introduce the sysvinit initialization manager.