Dynamic DNS for home routers.
https://karldns.de/api/v1/router/update/<secret>?myip=<ipaddr>
KarlDNS gives you a generated DynDNS hostname under karldns.de. Add the private update URL to your router, or use it from a script.
How it works
No account needed.
Create a hostname, save the private values, register it, done.
- CreateRandom hostname and private links.
- SaveCopy the secrets while they are shown.
- RegisterActivate the hostname when you are ready.
- UpdateRouter, cron, or CNAME can use it.
curl -sS 'https://karldns.de/api/v1/router/update/<secret>?myip=216.73.217.84'
good 216.73.217.84
Update from a router or script.
Works with FRITZ!Box, curl, cron, Home Assistant, OpenWrt, pfSense, OPNsense, UniFi, MikroTik, and custom tools.
# explicit IPv4
curl -sS 'https://karldns.de/api/v1/router/update/<secret>?myip=216.73.217.84'
# source IP fallback
curl -sS 'https://karldns.de/api/v1/router/update/<secret>'
Linux cron updater
Linux updater.
Run this on a Linux box that is always on. It creates and registers a hostname, installs the updater, schedules cron, and prints your private dashboard link. Works with Debian, Ubuntu, Fedora, Arch, Alpine, and Proxmox hosts.
Install
Sets up the updater and cron job.
curl -fsSL https://karldns.de/install.sh | sudo sh
Uninstall
Stops the updater and leaves private URLs on disk.
curl -fsSL https://karldns.de/uninstall.sh | sudo sh