This is cheatsheet on ddclient toward google domains.
1. install ddclient
sudo apt-get install ddclient
sudo apt-get install libio-socket-ssl-perl
2. config
after successful installation of ddclient edit the configuration file at /etc/ddclient.conf in your favorite editor
# Configuration file for ddclient generated by debconf #
# /etc/ddclient.conf
ssl=yes
#protocol=dyndns2
protocol=googledomains
use=web
server=domains.google.com
login=googledomaindyndnslogin password='autogeneratedpasswordformgoogle'
your.domain.com
daemon=100
sudo service ddclient restart
DEBUG
sudo ddclient -debug -verbose -noquiet