DO-DDNS

DO-DDNS is a dynamic DNS helper for Digital Ocean users to utilize their DO account as a Dynamic DNS resolver.

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Installation

Can be run bare metal or in docker. Docker is preferred, and will automatically run hourly unless configured otherwise.

Docker

1. Build the docker container with docker build . -t ddns
2. If ipv6 is needed, enable ipv6 by following the IPv6 instructions below.
3. Update the .env.sample file with api_key and other configuration options.
4. Start the container docker run --name ddns --rm --env-file=.env -d --restart=always ddns

Alternatively use the docker image:
docker run --name ddns --rm --env-file=.env -d --restart=always hunterreadca/do-ddns

Bare Metal

Set the env variable FREQUENCY to zero if using cron.

1. Copy the ddns.py file to /usr/local/bin and make it executable.
   chmod +x ddns.py
2. Run pip3 install -r requirements.txt to install all requirements.
3. Set the env variables with a script. (See below)
4. Setup a crontab. To run the app every 6 hours with cron add the following line to your crontab. Make sure you set the correct paths.
   0 */6 * * * /path/to/setenv && /usr/bin/python3 /path/to/ddns.py

Customization and Configuration

Environment variables

ENV Variable	Default	Description
API_KEY		Required Api Key to update DNS records
DOMAINS		Required JSON String of domains and subdomains. See below.
IPV4_SERVER	https://ipv4.icanhazip.com	Override the IP server lookup to use for ipv4
IPV6_SERVER	None	Override the IP server lookup to use for ipv6
FREQUENCY	3600	Frequency to run ddns update in seconds. Set to zeroe if the interval will be managed by cron.
TTL	3600	Record TTL

Domain config

Json String:

DOMAINS=[
    {
        "domain": "domain1.tld", 
        "subdomains": [
            "sub1.domain1.tld",
            "sub2.domain1.tld"
        ]
    },
    {
        "domain": "domain2.tld",
        ...
    }
]

See .env.sample for an example

IPv6 Support in Docker

Before you proceed, you will need a very recent docker installation, version 20.10.2 or later, recently merged with this pull-request. Otherwise, manually set-up SNAT using ip6tables, or try the other 2 approaches.

To enable ip6tables handling, the experimental flag must be enabled. Put the following in /etc/docker/daemon.json or adjust to fit:

{
	"ipv6": true,
	"fixed-cidr-v6": "fd00:ffff::/80",
	"ip6tables": true,
	"experimental": true
}

Then, restart the docker daemon:

sudo service docker restart.

Set Env Variables on Bare Metal

1. Create a file setenv
2. In the file export each env variable.

export API_KEY=<your_api_key>
export DOMAINS=<your_domains>