Dockerfile

FROM nginx

COPY nginx.conf /etc/nginx/nginx.conf

RUN cat /etc/resolv.conf

fly.toml

app = "nginx-scratch"

kill_signal = "SIGINT"
kill_timeout = 5

[experimental]
  private_network=true

[[services]]
  internal_port = 8085
  protocol = "tcp"

  [services.concurrency]
    hard_limit = 25
    soft_limit = 20

  [[services.ports]]
    handlers = ["http"]
    port = "80"

  [[services.ports]]
    handlers = ["tls", "http"]
    port = "443"

  [[services.tcp_checks]]
    grace_period = "1s"
    interval = "15s"
    port = "8085"
    restart_limit = 6
    timeout = "2s"

nginx.conf

events {
    worker_connections  1024;
    multi_accept off;
}

http {
    server {
        listen 8085 default_server;

        proxy_buffers 16 16k;
        proxy_buffer_size 16k;
        proxy_set_header Host $http_host;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_http_version 1.1;

        location / {
            resolver [fdaa::3]:53 valid=30s;
            set $upstream_service tinypilot._peer.internal;
            proxy_pass             http://$upstream_service:80;
            proxy_set_header       Host $http_host;
        }
    }
}