로딩...
forward-auth
user -> ingress -> backend service
user -> ingress -> forward auth service <- forward auth service -> backend service
X-Forward-[] 헤더들과 cookie 를 가지고 인증을 앞단에서 선 처리
traefik tutorial
[URL] https://radarr.example.com/_oauth [URL] https://radarr.example.com/_oauth