ipupdater

This program behaves like a DynDNS service for your own domain. It checks if your (dynamic) IP has changed and updates it as soon as differs from the set ip. https://api.ipify.org is used for getting your actual (dynamic) ip address. Check out their resources to learn more

Installation

• get a (free) account for NS1 DNS service (https://ns1.com/)
• create an API key
• Either copy config.json to /etc/ns1/config.json or use an environmental variable (see below)
• replace the API key in config.json

...
"key": "---putYourKeyhere---",
...

Docker

To run it with minimal settings, use:

docker build -t ipupdater .
docker run -d -e RECORDS="www.example.com;vpn.example.com" -e NS1_APIKEY="--NS1APKEY---" ipupdater

Possible env variables:

ENV variable	Description	DEFAULT	Mandatory
RECORDS	All resource records you want to have updated	"www.example.com;example.com"	Yes
QUERY_FREQUENCY	How long to wait before calling the API again and doing a fresh check (in seconds)	10	No
UPDATE_FREQUENCY	Update the IP address that is currently set in NS1 every so seconds	600	No
NS1_APIKEY	Pass your API Key via this env variable. The env variable has precedence over an existing conf file.	""	Yes for Docker; for daemon install you can use a config file as well
LOGLEVEL	One of DEBUG, INFO, WARNING, ERROR, CRITICAL	INFO	No

Run it as daemon with systemd

You have to install some python libraries

• ns1-python
• logging (likely installed by default)
• requests (likely installed by default)

To make this program run:

• copy ipupdater.py to /usr/sbin/ipupdater.py
• make ipudater.py executable

chmod +x /usr/sbin/ipupdater.py

• replace the resource records in ipupdater.py (or use an environtmental variable)

resource_records = ["example.net", "www.example.net"]

• make sure the resource record exist on NS1
• copy the ipudater.service file to /etc/systemd/system/ipudater.service
• Reload the systemd-daemon

systemctl daemon-reload

• start and enable ipupdater

systemctl start ipupdater
systemctl enable ipupdater

• You can see log entries with journalctl, as soon as the program runs.

In case of problems, try to increase the log level to find out where the error occurs.