Hola! I decided to put together this compare and contrast the boot order between SystemV and systemd. Contact me if you have any questions.
| Stage | SystemV (SysVinit) | systemd |
|---|---|---|
| Firmware start | BIOS or UEFI loads bootloader | BIOS or UEFI loads bootloader |
| Bootloader | GRUB loads kernel + initramfs | GRUB loads kernel + initramfs |
| Kernel start | Kernel initializes hardware | Kernel initializes hardware |
| First process | /sbin/init (PID 1) | /usr/lib/systemd/systemd (PID 1) |
| Config read | /etc/inittab | Unit files + generators |
| Default state | Runlevel (0–6) | Target (multi-user.target) |
| Startup method | Sequential shell scripts | Parallel unit activation |
| Ordering | Numeric prefixes (S10, S20) | Dependency graph |
| Service location | /etc/init.d/ | /usr/lib/systemd/system/ |
| Runlevel dirs | /etc/rc.d/rc*.d/ | /etc/systemd/system/ |
| Dependency handling | Manual, fragile | Automatic, strong |
| Boot speed | Slower | Faster |
| Logging | syslog | journal |
| Status tracking | Limited | Full state tracking |
Remember to stay strong and keep brewing great coffee at home!