External Ambassador

Utility that runs inside of the Kubernetes cluster that takes the host entries on ambassador mappings defined in service annotations and converts them to external-dns annotations on the ambassador service.

Dependencies

This requires a deployed Ambassador (getambassador.io) and External DNS (github.com/kubernetes-incubator/external-dns). Once both of those projects are deployed in the cluster this utility will automate the syncing of DNS to point at the ambassador service.

Deploy in Kubernetes

This just runs as a simple Deployment in the cluster. It will automatically watch for changes in the cluster and make the required adjustments so external-dns will pick up the changes.

All the examples assume that ambassador and external-dns are running the same namespace "ambassador".

With RBAC (most common)

---
apiVersion: v1
kind: ServiceAccount
metadata:
  name: external-ambassador
  namespace: ambassador
---
apiVersion: rbac.authorization.k8s.io/v1beta1
kind: ClusterRole
metadata:
  name: external-ambassador
rules:
- apiGroups: [""]
  resources: ["namespaces"]
  verbs: ["get","list"]
- apiGroups: [""]
  resources: ["services"]
  verbs: ["get","watch","list","update"]
---
apiVersion: rbac.authorization.k8s.io/v1beta1
kind: ClusterRoleBinding
metadata:
  name: external-ambassador-viewer
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: external-ambassador
subjects:
- kind: ServiceAccount
  name: external-ambassador
  namespace: ambassador
---
apiVersion: extensions/v1beta1
kind: Deployment
metadata:
  name: external-ambassador
  namespace: ambassador
spec:
  strategy:
    type: Recreate
  template:
    metadata:
      labels:
        app: external-ambassador
    spec:
      serviceAccountName: external-ambassador
      containers:
      - name: external-dns
        image: blakerouse/external-ambassador:latest
        args:
        - --namespace=ambassador

Without RBAC

---
apiVersion: extensions/v1beta1
kind: Deployment
metadata:
  name: external-ambassador
  namespace: ambassador
spec:
  strategy:
    type: Recreate
  template:
    metadata:
      labels:
        app: external-ambassador
    spec:
      containers:
      - name: external-dns
        image: blakerouse/external-ambassador:latest
        args:
        - --namespace=ambassador