https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/9623#note_24573655

lib/support/nginx/gitlab

@@ -42,7 +42,8 @@ server {
   ## http://nginx.org/en/docs/http/ngx_http_realip_module.html
   real_ip_header X-Real-IP; ## X-Real-IP or X-Forwarded-For or proxy_protocol
   real_ip_recursive off;    ## If you enable 'on'
-  set_real_ip_from YOUR_TRUSTED_ADDRESS; ## Replace this with something like 192.168.1.0/24
+  ## If you have a trusted IP address, uncomment it and set it
+  # set_real_ip_from YOUR_TRUSTED_ADDRESS; ## Replace this with something like 192.168.1.0/24
 
   ## Individual nginx logs for this GitLab vhost
   access_log  /var/log/nginx/gitlab_access.log;

lib/support/nginx/gitlab-ssl

@@ -86,7 +86,8 @@ server {
   ## http://nginx.org/en/docs/http/ngx_http_realip_module.html
   real_ip_header X-Real-IP; ## X-Real-IP or X-Forwarded-For or proxy_protocol
   real_ip_recursive off;    ## If you enable 'on'
-  set_real_ip_from YOUR_TRUSTED_ADDRESS; ## Replace this with something like 192.168.1.0/24
+  ## If you have a trusted IP address, uncomment it and set it
+  # set_real_ip_from YOUR_TRUSTED_ADDRESS; ## Replace this with something like 192.168.1.0/24
 
   ## Individual nginx logs for this GitLab vhost
   access_log  /var/log/nginx/gitlab_access.log;