I think this is the most suitable lecture for those who are building a cluster for the first time. Don't be afraid of the theory part at first, and if you don't understand it, you can understand it sufficiently in the code lab and increase your understanding of the system. It was good that I could build a cluster so easily while proceeding quickly and concisely. At this point, a 404 page appears when downloading and installing the package, but you can install it by going to the site and matching the appropriate version. I personally think it would be better if you updated it. I want to try attaching more diverse engines, loading data collected from outside, and visualizing it. I would be so grateful if you could create an additional lecture that connects Impala and Airflow to the built system!