External DNS Dynamic IP

Simple cron job that fixes external-dns when running behind a NAT with MetalLB.

By default, external-dns will inspect the value of a Service's external IP. If you use MetalLB and set up a port forward, this will not work as intended. External-dns will set DNS targets to your Service's internal IP instead of using your external IP.

This script will create a new ConfigMap called external-dns-dynamic-ip which will be updated dynamically if your IP changes. You can then assign this configmap to the EXTERNAL_DNS_DEFAULT_TARGETS external-dns env, and when your IP changes, the value will be updated and external-dns will be restarted so that it can update your DNS records.

Deployment

1. Deploy the Kustomization manifests:

   kubectl apply -k https://github.com/gabe565/external-dns-dynamic-ip//kustomization

2. Update your external-dns deployment with the following env:

   - name: EXTERNAL_DNS_DEFAULT_TARGETS
     valueFrom:
       configMapKeyRef:
         name: external-dns-dynamic-ip
         key: ip