Dynamic DNS Update

An application which updates the DNS records in your DNS providers when your external/internet-facing IP address changes.

Update checks can occur on a frequency specified in configuration.

Supported DNS providers

• DigitalOcean
• GoDaddy

Supported DNS record types

• Address (A)

More record types will be added at a later date.

Getting started

1. Pull the DDNSUpdate package from the DDNSUpdate Repository at GitHub.

   docker pull ghcr.io/thedanieldoyle/ddnsupdate:latest

2. Set up configuration using either config file, environment variables or Docker secrets.

3. Run the application using either Docker CLI or Docker Compose.

Docker CLI

• The following is an example using config.json file configuration and docker run.

  docker run -d --name ddnsupdate -v /apps/ddnsupdate/config.json:/app/config.json ghcr.io/thedanieldoyle/ddnsupdate:latest

Docker-Compose

• The following is an example using docker-compose.

  docker-compose up -d

• See the Docker sample folder for an example of a docker-compose.yml file.

Configuration

DDNSUpdate supports three configuration types (all three may be used at the same time):

• Configuration file
• Environment variables
• Docker secrets

The easiest to set up and use is the configuration file. It is possible however to keep all non-sensitve configuration in a configuration file and use Docker secrets or environment variables to configure senstive values.

File configuration

• The config.json or config.yml/yaml must be bound using a bind mount if you are using file configuration.
• See the Configuration sample folder for examples of config.json and config.yml/yaml file configuration.
• The config.json or config.yml/yaml must be bound in the container to either:
  • /app/config.json
  • /app/config.yml
  • /app/config.yaml

Environment Variable configuration

• The following example configures two External Address providers.

  ExternalAddressProviders__0__Uri=https://bot.whatismyipaddress.com/ ExternalAddressProviders__1__Uri=https://ipv4bot.whatismyipaddress.com/

• See ASP.NET Core Environment configuration for instructions on how to structure the Environment Variable names.

Docker Secrets configuration

• As with the environment variables, name your Docker Secrets the same way.

  printf "https://bot.whatismyipaddress.com/" | docker secret create ExternalAddressProviders__0__Uri -

  printf "https://ipv4bot.whatismyipaddress.com/" | docker secret create ExternalAddressProviders__1__Uri -

• See ASP.NET Core Key-per-file configuration for instructions on how to structure the Docker Secret names.

Build docker image

DDNSUpdate supports multi-platform builds with buildx, post dotnet SDK verison 7.0.300.

Example build for Linux AM64 and ARM64

Replace REGISTRY with your own if you are pushing to a Docker registry.

export DOCKERFILE=DDNSUpdate/Dockerfile;
export REGISTRY=ghcr.io/thedanieldoyle;
export SERVICE=ddnsupdate;
export VERSION=1.0.0;
docker buildx build --platform linux/amd64,linux/arm64 --tag "${REGISTRY}/$SERVICE:$VERSION" --build-arg VERSION --file $DOCKERFILE --push .

To support multi-platform builds, changes were required to the dotnet SDK from Microsoft, and also use of some automatic ARGs from Docker. Namely BUILDPLATFORM and TARGETARCH. See Docker documentation.

Also, the build command above will attempt to push to your docker registry using --push, therefore be sure to log in first.

If you just want to build an image for local development, change --push to --load.

Fun fact

You may notice on the docker buildx build command, the --build-arg VERSION is not using the variable with $ symbol, as set above. This is by design. The Docker documentation explains.

You may also use the --build-arg flag without a value, in which case the value from the local environment will be propagated into the Docker container

As the variable in the shell scope and inside the Dockerfile are the same name, you don't need to specify it in VERSION=$VERSION syntax when building. Neat!

Authors

• Daniel P. Doyle - TheDanielDoyle
• Adam Parker - ParkerAdam
• Michael Willis - Mickey-Willis

See also the list of contributors who participated in this project.

Acknowledgements

We would like to thank the following open source projects.

Project	Repository	License
Ardalis.SmartEnum	https://github.com/ardalis/SmartEnum	LICENSE
AutoMapper	https://github.com/AutoMapper/AutoMapper	LICENSE
FakeItEasy	https://github.com/FakeItEasy/FakeItEasy	LICENSE
FluentResults	https://github.com/altmann/FluentResults	LICENSE
FluentValidation	https://github.com/FluentValidation/FluentValidation	LICENSE
Flurl	https://github.com/tmenier/Flurl	LICENSE
NetEscapades.Configuration	https://github.com/andrewlock/NetEscapades.Configuration	LICENSE
Newtonsoft.Json	https://github.com/JamesNK/Newtonsoft.Json	LICENSE
Serilog	https://github.com/serilog/serilog	LICENSE
xunit	https://github.com/xunit/xunit	LICENSE
YamlDotNet	https://github.com/aaubry/YamlDotNet	LICENSE

License

This project is licensed under the MIT License - see the LICENSE file for details.