Below is a short Linux boot troubleshooting flowchart I put together. Its mainly for my own reference and also to share it with anyone wanting to learn. After brewing a good cup of Caturra coffee at home. I put together this simple flowchart:
[ Start ]
↓
[ Power on the system ]
↓
[ BIOS/UEFI screen appears? ]
├─ No → Check power, motherboard, or display
└─ Yes
↓
[ Is boot device detected (e.g., disk)? ]
├─ No → Check BIOS/UEFI settings & boot order
└─ Yes
↓
[ GRUB menu appears? ]
├─ No → Reinstall GRUB using live CD/USB
└─ Yes
↓
[ Can you boot a kernel from GRUB? ]
├─ No → Use GRUB shell (grub>) to find kernel & initrd
└─ Yes
↓
[ Kernel loads or shows panic? ]
├─ Panic → Check for missing initramfs or incorrect root
└─ Loads
↓
[ System hangs or gives error after kernel load? ]
├─ Yes → Inspect initramfs and boot logs
└─ No
↓
[ Reaches login screen or prompt? ]
├─ No → Check systemd/journalctl logs (journalctl -xb)
└─ Yes → System boot successful
Let me know what you think in the comments section below. I also have a few ITPro Helper IT T-Shirts and coffee mugs in my shop. If you like any you can place an order. Thanks!