upstream prematurely closed connection while reading response header from upstream

k8s 서버에서 upstream prematurely closed connection while reading response header from upstream 이런 메시지가 나오는데 .. 왜그런지는 모르겟고 일단 참고 url 만 써놓는다.

 

https://github.com/Kong/kong/issues/3785 

https://stackoverflow.com/questions/36488688/nginx-upstream-prematurely-closed-connection-while-reading-response-header-from