nginx: configuration file /etc/nginx/nginx.conf test failed (host not found in upstream)
All you need is to put resolver that can resolve such domain name: resolver 8.8.8.8 valid=300s; resolver_timeout 10s; Google DNS (8.8.8.8) can resolve it, but it resolves to internal address belongs to network class C. $ dig @8.8.8.8 www.class.com.192.168.33.10.xip.io ;; ANSWER SECTION: www.class.com.192.168.33.10.xip.io. 299 IN A 192.168.33.10