Verify your External DNS Configuration

This page contains commands to verify that the external-dns service is functioning correctly.

If the external-dns service is not working properly, these commands also provide aids to find the cause or identify the issue.

Verify the Deployment

Verify that the deployment was triggered.

1. Set the environment variable to the Management/Essential cluster by exporting the kubeconfig file in your terminal window or using the --kubeconfig=${CLUSTER_NAME}.conf as explained in Provide Context for Commands with a kubeconfig File.

2. Verify that the external-dns deployment is present:
   Replace <target_WORKSPACE_NAMESPACE> in the namespace -n flag with the target cluster’s workspace namespace.

   CODE

   kubectl get appdeployments.apps.kommander.d2iq.io -n <target_WORKSPACE_NAMESPACE> external-dns

   The output should look like this:

   CODE

   NAME           APP                          AGE
   external-dns   external-dns-<app_version>   36s

   The CLI has triggered the deployment of the application. However, this does not mean that the application has been installed completely and successfully.

Verify that the deployment was successful.

1. Set the environment variable to the target cluster (where you enabled external-dns) by exporting the kubeconfig file in your terminal window or using the --kubeconfig=${CLUSTER_NAME}.conf as explained in Provide Context for Commands with a kubeconfig File.

2. Verify that the external-dns deployment is ready:
   Replace <target_WORKSPACE_NAMESPACE> in the namespace -n flag with the target cluster’s workspace namespace.

   CODE

   kubectl get deployments.apps -n <target_WORKSPACE_NAMESPACE> external-dns

   The deployment should display a ready state:

   CODE

   NAME           READY   UP-TO-DATE   AVAILABLE   AGE
   external-dns   1/1     1            1           42s

   The CLI has deployed the application completely and successfully.

Examine the Cluster’s Ingress

1. Set the environment variable to the target cluster (where you enabled external-dns) by exporting the kubeconfig file in your terminal window or using the --kubeconfig=${CLUSTER_NAME}.conf as explained in Provide Context for Commands with a kubeconfig File.

2. Verify that the cluster’s ingress contains the correct hostname annotation:
   Replace <target_WORKSPACE_NAMESPACE> in the namespace -n flag with the target cluster’s workspace namespace.

   CODE

   kubectl get services -n <target_WORKSPACE_NAMESPACE> kommander-traefik -o yaml

   The output looks like this:
   Ensure that the service object contains the external-dns.alpha.kubernetes.io/hostname: <mycluster.example.com> annotation.

   CODE

   apiVersion: v1
   kind: Service
   metadata:
     annotations:
       meta.helm.sh/release-name: kommander-traefik
       meta.helm.sh/release-namespace: kommander
       external-dns.alpha.kubernetes.io/hostname: <mycluster.example.com>
     creationTimestamp: "2023-06-21T04:52:49Z"
     finalizers:
   [...]

   The external-dns service has been linked to the cluster correctly.

Verify the DNS Record

It can take a few minutes for the external-dns service to create a DNS record. The delay depends on your cloud provider.

Verify that the external-dns service has created a DNS record.

1. Set the environment variable to the target cluster (where you enabled external-dns) by exporting the kubeconfig file in your terminal window or using the --kubeconfig=${CLUSTER_NAME}.conf as explained in Provide Context for Commands with a kubeconfig File.

2. Access and execute the required image:

   CODE

   kubectl run -it --image=nicolaka/netshoot --rm test-dns -- /bin/bash

3. Use the image to check your domain and see the record:
   Replace <mycluster.example.com> with the domain you assigned to your target cluster.

   CODE

   nslookup <mycluster.example.com>

   The output should look like this:

   CODE

   Server:		192.168.178.1
   Address:	192.168.178.1#53
   
   Non-authoritative answer:
   Name:	<mycluster.example.com>
   Address: 134.568.789.12

   The external-dns service is working and the DNS provider recognizes the record created by the service. If the command displays an error, the configuration is failing on the end of the DNS provider.