I am using HDP 3.0.1 (VirtualBox), what I did is: (1) login: ssh -p 2122 root@localhost (2) add following code in http-hdp.proxy (for NiFi) (3) docker restart sandbox-proxy and then same issue showed up:  [emerg] 1#1: host not found in upstream "sandbox-hdp" in /etc/nginx/conf.d/http-hdp.conf:9 nginx: [emerg] host not found in upstream "sandbox-hdp" in /etc/nginx/conf.d/http-hdp.conf:9   There's only 2 containers, sandbox-proxy and sandbox-hdp-security, and there's no http-hdp.conf under /etc/nginx/conf.d   ... View more