How is Cache-Control: max-age affected by intermediate caching

I actually work for CloudFlare & thought I would jump in.

-Please keep in mind that caching will take a few days to build out & it depends on the number of requests for the static resources.

-Another thing to keep in mind that we would only proxy what you have set in your DNS settings (orange cloud on the subdomain). If you have an images or CDN subdomain, for example, you would want to make sure it is both added in CloudFlare & covered with an orange cloud.

Have you tried Cache-Control flags in your nginx configuration ?

Sample configuration:

upstream yourappserver{
  server 0.0.0.0:6677;
}


proxy_cache_path  /tmp/cache levels=1:2 keys_zone=my-test-cache:8m max_size=5000m inactive=300m;

server {
    listen 80;
    server_name your.domain.tld;
    root /path/to/the/document/root/;

    access_log  /var/log/nginx/access.log;

    location / {
      proxy_set_header X-Real-IP $remote_addr;
      proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
      proxy_set_header Host $http_host;
      proxy_cache my-test-cache;
      proxy_cache_valid  200 404  1m;
      proxy_cache_valid 302 20m;

      proxy_cache_use_stale   error timeout invalid_header updating;
      proxy_redirect off;

      if (-f $request_filename/index.html) {
        rewrite (.*) $1/index.html break;
      }
      if (-f $request_filename.html) {
        rewrite (.*) $1.html break;
      }
      if (!-f $request_filename) {
        proxy_pass http://yourappserver;
        break;
      }
    }

    error_page 500 502 503 504 /50x.html;
    location = /50x.html {
      root html;
    }
}

I think you are looking for this particular configuration snippet

proxy_cache_valid 302 20m;