kexec (reboot without hardware initialization)

echo "kexec-tools kexec-tools/load_kexec select true" | sudo debconf-set-selections
 
sudo apt install -y kexec-tools
#sudo kexec -l /boot/vmlinuz-4.15.0-32-generic --initrd=/boot/initrd.img-4.15.0-32-generic --reuse-cmdline
#sudo kexec -e
#systemctl kexec
 
sudo kexec -l /vmlinuz --initrd=/initrd.img --reuse-cmdline && sudo systemctl kexec

 - name: Enable kexec
   lineinfile:
     path: /etc/default/kexec
     regexp: '^LOAD_KEXEC='
     line: 'LOAD_KEXEC=true'
   when: ('dev' in group_names)

wget http://archive.ubuntu.com/ubuntu/dists/bionic/main/installer-amd64/current/images/netboot/mini.iso
sudo kexec -l /mnt/linux --initrd=/mnt/initrd.gz
sudo systemctl kexec