LambdaDyn

A dynamic DNS solution running on AWS Lambda and Route53.

Requirements

• Node >= 20 installed and active.
• A Linux server (tested on Ubuntu) that you want to run this from.

A build script is provided to build an OSX client, however, no installation scripts are provided like with Linux.

Setup Cloud Infrastructure

Ensure you are authenticated with AWS.
https://www.serverless.com/framework/docs/providers/aws/guide/credentials

Provision a public hosted zone in Route53.
https://docs.aws.amazon.com/Route53/latest/DeveloperGuide/CreatingHostedZone.html

Create a .env file with the following contents:

HOSTED_ZONE_ID=id-of-your-hosted-zone

Install via Serverless:

npm install
npm run dp:dev

This will deploy all the infrastructure including the API gateway and lambda functions.

Setup Client

Currently supports Linux (tested on Ubuntu). Since I don't yet publish prebuilt binaries, you'll have to build this on the host Linux machine. Ensure at least Node 20 is installed and active, and you have this repository cloned. Then:

npm install
./build-linux.sh

This will build a zip file with built binaries as well as some install and uninstall scripts.

cd ~
cp lambda-dyn/.pkg/lambdadyn-client.zip
unzip lambdadyn-client.zip -d client

cd client
./install.sh

Install script will create a sytsemctl service, install the binary to the /bin directory, ensure /var/log/lambdadyn is present, and copy a sample config to /etc/lambdadyn/config.json

Grab the API GW invocation url as well as the API Key that was created as part of the Serverless deploy.

Update the /etc/lambdadyn/config.json file:

{
  "dynServerUrl": "your-apigw-url",
  "apiKey": "your-api-key",
  "logsDir": "/var/log/lambdadyn",
  "hosts": [
    "your-hosts-you-want-updated, e.g. app.test.com"
  ]
}

Start the service:

sudo systemctl start lambdadyn.service

Uninstalling Client

Stopping the service

sudo systemctl stop lambdadyn.service

Uninstall completely

The zipped package contains an uninstall script that will remove lambdadyn entirely.

Logging

Client logs can be found at /var/log/lambdadyn. They're rotated daily.

Infrastructure Cleanup

To cleanup created Cloudformation resources, run:

npm run dy:dev

Note, this will leave behind hosted zone records, you will have to clean those up by hand.