hermes-config/skills/vps-reverse-proxy/references/duckdns-vps-ip.md

DuckDNS VPS Routing Fix

When routing grajmedia.duckdns.org through the VPS reverse proxy, the DuckDNS update script MUST target the VPS IP, not auto-detect the home server IP.

Problem

The DuckDNS update script at /opt/duckdns/update.sh used &ip= (empty, auto-detect), so DuckDNS recorded the home server's public IP (162.81.173.34) instead of the VPS IP (51.81.84.34). Traffic was bypassing the VPS entirely.

Fix

Hard-code the VPS IP in the update script:

#!/bin/bash
echo url="https://www.duckdns.org/update?domains=grajmedia&token=TOKEN&ip=51.81.84.34" | curl -k -s -o /opt/duckdns/duck.log -K -

Also check /etc/hosts for local overrides like 127.0.0.1 grajmedia.duckdns.org (kept for local access to avoid hairpin NAT).