Setting up External-DNS for Services on Akamai Edge DNS¶

Prerequisites¶

External-DNS v0.8.0 or greater.

Zones¶

External-DNS manages service endpoints in existing DNS zones. The Akamai provider does not add, remove or configure new zones. The Akamai Control Center or Akamai DevOps Tools, Akamai CLI and Akamai Terraform Provider can create and manage Edge DNS zones.

Akamai Edge DNS Authentication¶

The Akamai Edge DNS provider requires valid Akamai Edgegrid API authentication credentials to access zones and manage DNS records.

Either directly by key or indirectly via a file can set credentials for the provider. The Akamai credential keys and mappings to the Akamai provider utilizing different presentation methods are:

Edgegrid Auth Key	External-DNS Cmd Line Key	Environment/ConfigMap Key	Description
host	akamai-serviceconsumerdomain	EXTERNAL_DNS_AKAMAI_SERVICECONSUMERDOMAIN	Akamai Edgegrid API server
access_token	akamai-access-token	EXTERNAL_DNS_AKAMAI_ACCESS_TOKEN	Akamai Edgegrid API access token
client_token	akamai-client-token	EXTERNAL_DNS_AKAMAI_CLIENT_TOKEN	Akamai Edgegrid API client token
client-secret	akamai-client-secret	EXTERNAL_DNS_AKAMAI_CLIENT_SECRET	Akamai Edgegrid API client secret

In addition to specifying auth credentials individually, an Akamai Edgegrid .edgerc file convention can set credentials.

External-DNS Cmd Line	Environment/ConfigMap	Description
akamai-edgerc-path	EXTERNAL_DNS_AKAMAI_EDGERC_PATH	Accessible path to Edgegrid credentials file, e.g /home/test/.edgerc
akamai-edgerc-section	EXTERNAL_DNS_AKAMAI_EDGERC_SECTION	Section in Edgegrid credentials file containing credentials

Akamai API Authentication provides an overview and further information about authorization credentials for API base applications and tools.

Deploy External-DNS¶

An operational External-DNS deployment consists of an External-DNS container and service. The following sections demonstrate the ConfigMap objects that would make up an example functional external DNS kubernetes configuration utilizing NGINX as the service.

Connect your kubectl client to the External-DNS cluster, and then apply one of the following manifest files:

Manifest (for clusters without RBAC enabled)¶

apiVersion: apps/v1
kind: Deployment
metadata:
  name: external-dns
spec:
  strategy:
    type: Recreate
  selector:
    matchLabels:
      app: external-dns
  template:
    metadata:
      labels:
        app: external-dns
    spec:
      serviceAccountName: external-dns
      containers:
      - name: external-dns
        image: k8s.gcr.io/external-dns/external-dns:v0.8.0
        args:
        - --source=service  # or ingress or both
        - --provider=akamai
        - --domain-filter=example.com
        # zone-id-filter may be specified as well to filter on contract ID
        - --registry=txt
        - --txt-owner-id={{ owner-id-for-this-external-dns }}
        - --txt-prefix={{ prefix label for TXT record }}.
        env:
        - name: EXTERNAL_DNS_AKAMAI_SERVICECONSUMERDOMAIN
          valueFrom:
            secretKeyRef:
              name: external-dns
              key: EXTERNAL_DNS_AKAMAI_SERVICECONSUMERDOMAIN
        - name: EXTERNAL_DNS_AKAMAI_CLIENT_TOKEN
          valueFrom:
            secretKeyRef:
              name: external-dns
              key: EXTERNAL_DNS_AKAMAI_CLIENT_TOKEN
        - name: EXTERNAL_DNS_AKAMAI_CLIENT_SECRET
          valueFrom:
            secretKeyRef:
              name: external-dns
              key: EXTERNAL_DNS_AKAMAI_CLIENT_SECRET
        - name: EXTERNAL_DNS_AKAMAI_ACCESS_TOKEN
          valueFrom:
            secretKeyRef:
              name: external-dns
              key: EXTERNAL_DNS_AKAMAI_ACCESS_TOKEN

Manifest (for clusters with RBAC enabled)¶

apiVersion: v1
kind: ServiceAccount
metadata:
  name: external-dns
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
  name: external-dns
rules:
- apiGroups: [""]
  resources: ["services","endpoints","pods"]
  verbs: ["get","watch","list"]
- apiGroups: ["extensions","networking.k8s.io"]
  resources: ["ingresses"]
  verbs: ["get","watch","list"]
- apiGroups: [""]
  resources: ["nodes"]
  verbs: ["watch", "list"]
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
  name: external-dns-viewer
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: external-dns
subjects:
- kind: ServiceAccount
  name: external-dns
  namespace: default
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: external-dns
spec:
  strategy:
    type: Recreate
  selector:
    matchLabels:
      app: external-dns
  template:
    metadata:
      labels:
        app: external-dns
    spec:
      serviceAccountName: external-dns
      containers:
      - name: external-dns
        image: k8s.gcr.io/external-dns/external-dns:v0.8.0
        args:
        - --source=service  # or ingress or both
        - --provider=akamai
        - --domain-filter=example.com
        # zone-id-filter may be specified as well to filter on contract ID
        - --registry=txt
        - --txt-owner-id={{ owner-id-for-this-external-dns }}
        - --txt-prefix={{ prefix label for TXT record }}.
        env:
        - name: EXTERNAL_DNS_AKAMAI_SERVICECONSUMERDOMAIN
          valueFrom:
            secretKeyRef:
              name: external-dns
              key: EXTERNAL_DNS_AKAMAI_SERVICECONSUMERDOMAIN
        - name: EXTERNAL_DNS_AKAMAI_CLIENT_TOKEN
          valueFrom:
            secretKeyRef:
              name: external-dns
              key: EXTERNAL_DNS_AKAMAI_CLIENT_TOKEN
        - name: EXTERNAL_DNS_AKAMAI_CLIENT_SECRET
          valueFrom:
            secretKeyRef:
              name: external-dns
              key: EXTERNAL_DNS_AKAMAI_CLIENT_SECRET
        - name: EXTERNAL_DNS_AKAMAI_ACCESS_TOKEN
          valueFrom:
            secretKeyRef:
              name: external-dns
              key: EXTERNAL_DNS_AKAMAI_ACCESS_TOKEN

Create the deployment for External-DNS:

$ kubectl apply -f externaldns.yaml

Deploying an Nginx Service¶

Create a service file called ‘nginx.yaml’ with the following contents:

apiVersion: apps/v1
kind: Deployment
metadata:
  name: nginx
spec:
  selector:
    matchLabels:
      app: nginx
  template:
    metadata:
      labels:
        app: nginx
    spec:
      containers:
      - image: nginx
        name: nginx
        ports:
        - containerPort: 80
---
apiVersion: v1
kind: Service
metadata:
  name: nginx
  annotations:
    external-dns.alpha.kubernetes.io/hostname: nginx.example.com
    external-dns.alpha.kubernetes.io/ttl: "600" #optional
spec:
  selector:
    app: nginx
  type: LoadBalancer
  ports:
    - protocol: TCP
      port: 80
      targetPort: 80

Create the deployment and service object:

$ kubectl apply -f nginx.yaml

Verify Akamai Edge DNS Records¶

Wait 3-5 minutes before validating the records to allow the record changes to propagate to all the Akamai name servers.

Validate records using the Akamai Control Center or by executing a dig, nslookup or similar DNS command.

Cleanup¶

Once you successfully configure and verify record management via External-DNS, you can delete the tutorial’s examples:

$ kubectl delete -f nginx.yaml
$ kubectl delete -f externaldns.yaml

Additional Information¶

The Akamai provider allows the administrative user to filter zones by both name (domain-filter) and contract Id (zone-id-filter). The Edge DNS API will return a ‘500 Internal Error’ for invalid contract Ids.
The provider will substitute quotes in TXT records with a ` (back tick) when writing records with the API.

Last update: June 23, 2021