nginx-rails5.conf

upstream app {
  server 127.0.0.1:3000;
}

server {
  listen 80;
  server_name localhost;

  location / {
    proxy_read_timeout 600;
    proxy_pass http://app;
    # What follows is required for WebSockets
    proxy_http_version 1.1;
    proxy_set_header Upgrade $http_upgrade;
    proxy_set_header Connection $connection_upgrade;
  }
}