If you have a Zyxel 5501 router, you may use the Update URL option in the router
to update IP address for your domain name.
Log into the web interface of your router and go to Internet then Additional Features then Dynamic DNS, you can apply these setting:

Log into the web interface of your router and go to Internet then Additional Features then Dynamic DNS, you can apply these setting:
- Provider: Update URL
- Server Address: https://api.dynu.com/nic/update?hostname=<domain>&password=<password>&myip=<ipaddr>
- Expected Server Response: g. The correct server response could be good yourcurrentip or nochg. The router did not provide an option to enter 2 possible answers so we will put g which is a common character for 2 answers.
- Domain Name: enter your hostname, for example, example.dynu.com or example.com
- Account Name: enter your Dynu username, which could be found in Contact Details in the control panel
- Password: enter your Dynu password or IP update password. MD5 or SHA256 of the password is also accepted on our server side.
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