hafeez@unixshadow:~$ journalctl –list-boots | head -1 # what actually happens at boot
Linux Boot Sequence
From Power-On to Login Prompt
seven stages, as the kernel would tell it — no steps skipped.
[1/7] FIRMWARE — UEFI takes over
[ 0.000][ OK ] Power-On Self-Test: CPU, RAM and devices probed and initialized.
[ 0.412][ OK ] Boot entries read from NVRAM;
grubx64.efi loaded from /boot/efi.[2/7] BOOTLOADER — GRUB 2
[ 0.988][ OK ]
/boot/grub2/grub.cfg parsed; boot menu rendered.[ 1.204][ OK ] Kernel + initramfs loaded into memory; command line (root=, quiet, …) passed along.
[3/7] KERNEL LOAD — vmlinuz takes the CPU
[ 1.310][ OK ]
/boot/vmlinuz-* decompressed; control transferred from GRUB.[ 1.455][ OK ]
/boot/initramfs-*.img unpacked — early userspace with the drivers needed to find your disks.[4/7] KERNEL INIT — start_kernel()
[ 1.520][ OK ] Memory management, scheduler and device drivers up.
[ 2.031][ OK ] Real root mounted;
switch_root pivots off the initramfs.[ 2.033][INFO] Full story in the ring buffer:
dmesg.[5/7] INIT SYSTEM — systemd, PID 1
[ 2.140][ OK ] Kernel executes
/sbin/init → systemd becomes the first userspace process.[ 2.188][ OK ] Default target read — usually
multi-user.target or graphical.target — units start in parallel, honoring dependencies.[6/7] TARGETS — userspace comes alive
[ 3.042][ OK ]
sysinit.target: mounts, udev, hostname, machine ID.[ 4.317][ OK ]
basic.target → multi-user.target: networking, sshd, cron, logging — daemons online.[7/7] LOGIN — runtime reached
[ 5.009][ OK ]
getty spawned on virtual consoles; login prompt ready.[ 5.010][ OK ] Reached
multi-user.target. Authenticate, get a shell — system is fully at runtime.$ ls — key files
$
/boot/efi/EFI/*/grubx64.efi$
/boot/grub2/grub.cfg$
/boot/vmlinuz-*$
/boot/initramfs-*.img$
/etc/fstab$ — key commands
$
dmesg | less$
journalctl -b$
systemd-analyze blame$
systemctl get-default# root tip: slow boot?
systemd-analyze blame shows which units ate your boot time;systemd-analyze critical-chain finds the chain holding everything up.unixshadow.com · VPS & hosting from the shadowshafeez@unixshadow:~$