Here is an example of the proxy_pass config, we don't use IP's proxy_pass https://example.com; When "example.com" changes the IP address, it is not reflected in nginx. We're using k8s pods. Sometime one or two pods have stale DNS cache. Other pods work fine... Posted at Nginx Forum: https://forum.nginx.org/read.php?2,291252,291255#msg-291255