Part 4 · Lesson 16 · Expert

Boot — the ignition chain

Watch the machine wake up.

In this interactive Linux lesson from Stencel Academy you don't just read — you type real commands like dmesg and watch the machine respond on a live, animated map. It is part of the free How Linux Works course.

Key takeaway: Boot is a relay: firmware starts the bootloader, which starts the kernel, which starts systemd, which starts you.

Before this lesson

Builds on: Scheduling & Context Switch.

What you'll practise

systemd-analyze — Where boot time actually went.
cat /proc/cmdline — The arguments GRUB handed the kernel.
journalctl -b — This boot's full log.

Terms you'll learn

firmware (UEFI)bootloader (GRUB)initdmesgboot

Check your understanding

What loads and starts the kernel at boot?

The bootloader (GRUB)
systemd
Your shell

Open the interactive lesson →