ProxCP NAT Domain Forwarding
From ProxCP Documentation
On NAT nodes, ProxCP uses nginx reverse proxy to forward HTTP and HTTPS traffic to NAT virtual machines via domain names.
Default Web Page
ProxCP includes a default web page on NAT Proxmox nodes. This page is displayed if there is no valid nginx proxy configuration for a given domain. You can edit this default web page (/var/www/html/index.html) to anything you want.
Domain Deny List
ProxCP Daemon ships with a /nat/deny-domains.txt file. Any domains in this list cannot be forwarded for NAT by ProxCP users. The format is one unique domain per line.