2020-10-01 ML: add config file for IngressDNSRecord to create a Multi-Cluster Ingress DNS mechanism

ingressDNSRecord/ingressdnsrecord.yaml

+# ingressdnsrecord.yaml
+apiVersion: multiclusterdns.kubefed.io/v1alpha1
+kind: IngressDNSRecord
+metadata:
+  name: fed-helloworld-ingress
+  namespace: fed-namespace
+spec:
+  hosts:
+  - helloworld.<domain>
+  recordTTL: 300