dynup is a DDNS updater implemented in Bash. It pings a single webserver for an external IP address periodically, determines change and appropriately updates the DNS of your server. This was primarily designed to get around the issue of a router being incapable of easily supplying an external IP address to an internal user.
My script only requires a FreeDNS update URL. While this is safer than parsing login credentials, be aware that anyone with the update URL can redirect the domain name.
- Script can detach from terminal and run in background (technically not a daemon)
- Event logging
- No login credentials required
- Simple systemd setup
Make the file executable (if it isn't already) using:
chmod +x dynup
And run with your personalized FreeDNS 'Direct URL' DNS update link:
dynup -q <url>
Use systemd-setup.sh to set dynup as a systemd service. Alternatively, you can edit the included dynup-template.service file yourself.
Usage: dynup [-d|-h|-v][-f <int>][-l <str>][-q <str>]
-d Detach process and run in background.
-f Update frequency (seconds).
-h Show this help message.
-l Log updates to a file.
-q FreeDNS update url.
-v Increase verbosity.
- Multiple test webservers
- Track multiple DNS entries
- Alternative/safer methods to the update process
- Additional security methods (enforcing HTTPS)