Kexec

First off, what is kexec? - It is a system call that enables you to load and boot into another kernel from currently running kernel. That effectively means; doing reboot without going through the whole POST/Firmware load process. To use kexec we can rely on systemd to handle process for us. The only work we need to do is to install kexec-tools package and adjust some configs sudo apt-get update sudo apt-get install kexec-tools Since Ubuntu usually relies on booting from grub we can tweak some settings to default to loading default grub kernel when we run kexec. That is usually set to latest kernel we have installed and is automatically adjusted after system upgrade. Contents of my /etc/default/kexec are as follows: ...