Kernel panic

Occasionally, the Linux kernel hits a situation it just cannot handle and, ignoring the advice on the cover of the greatest book ever written, it panics. This manifests itself as a cryptic message to the console (or hidden behind a pretty boot splash screen if you are really unlucky) and a blinking caps lock LED. If it has got as far as mounting the root filesystem read/write, it can also write diagnostic information to the disk: a ‘core dump’.