linux.hankelsner

Field notes for Ubuntu

Boot failures, GRUB surprises, and the fixes that actually stick

Write-ups from real Ubuntu systems — dual-boot, NVMe, missing initrd, and how to get a clean default boot again without guesswork.

Illustration of the Ubuntu boot path from GRUB to a mounted NVMe root filesystem

Guide

Fix Ubuntu kernel panic: VFS unable to mount root fs on unknown-block(0,0)

What that panic really means, why a missing initrd breaks NVMe boots, and how to recover with Advanced options, initramfs, and safer GRUB defaults.