https://blog.dudaji.com/kubernetes/2019/08/18/k8s-create-cluster.html
https://www.youtube.com/watch?v=HYGUz9mC7Hg
http://www.kwangsiklee.com/2018/11/kubernetes%EC%97%90%EC%84%9C-ingress%EC%97%90-sslhttps-%EC%A0%81%EC%9A%A9%ED%95%98%EA%B8%B0/
인그레스 SSL 처리
https://github.com/kubernetes/kube-state-metrics
https://www.youtube.com/watch?v=voAyroDb6xk