nginx - read custom header from upstream server

Question

I am using nginx as a reverse proxy and trying to read a custom header from the response of an upstream server (Apache) without success. The Apache response is the following

Answer 1

I was facing the same issue. I tried both $http_my_custom_header and $sent_http_my_custom_header but it did not work for me.

Although solved this issue by using $upstream_http_my_custom_header.