Linux Boot Process
Explained (Step by Step)
When you power on your Linux PC, a lot happens before you reach the login screen. Let’s break it down.
BIOS/UEFI Initialization Your system firmware wakes up the hardware and runs the Power-On Self Test (POST).
Bootloader Stage (GRUB / LILO / systemd-boot) The bootloader loads the kernel image and initial RAM disk (initrd).
Kernel Initialization The Linux kernel takes charge, setting up CPU, memory, and hardware drivers.
Initramfs Temporary root filesystem that helps load real system files.
Init / Systemd Process The first process (PID 1) starts. It’s the parent of all other processes.
System Services & Daemons Background services (network, sound, display, etc.) start running.
Login Finally, you reach the login screen and can start using your system.
Without this chain, your Linux OS won’t even boot. Every step is essential!
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