Describe setting coredns server in nameserver resolv chain

docs/tasks/federation/set-up-coredns-provider-federation.md

@@ -97,9 +97,11 @@ coredns-provider.conf has below format:
     [Global]
     etcd-endpoints = http://etcd-cluster.my-namespace:2379
     zones = example.com.
+    coredns-endpoints = <coredns-server-ip>:<port>
 
  - `etcd-endpoints` is the endpoint to access etcd.
  - `zones` is the federation domain for which CoreDNS is authoritative and is same as --dns-zone-name flag of `kubefed init`.
+ - `coredns-endpoints` is the endpoint to access coredns server. This is an optional parameter introduced from v1.7 onwards.
 
 *Note: middleware.etcd.zones in CoreDNS configuration and --dns-zone-name
 flag to kubefed init should match.*
@@ -107,6 +109,10 @@ flag to kubefed init should match.*
 
 ## Setup CoreDNS server in nameserver resolv.conf chain
 
+*Note: Following section applies only to versions prior to v1.7 and
+will be automatically taken care if the `coredns-endpoints` parameter
+is configured in `coredns-provider.conf` as described in section above.
+
 Once the federation control plane is deployed and federated clusters
 are joined to the federation, you need to add the CoreDNS server to the
 pod's nameserver resolv.conf chain in all the federated clusters as this
@@ -118,9 +124,6 @@ achieved by adding the below line to `dnsmasq` container's arg in
 
 Replace `example.com` above with federation domain.
 
-*Note: Adding CoreDNS server to the pod's nameserver resolv.conf chain will be
-automated in subsequent releases.*
-
 
 Now the federated cluster is ready for cross-cluster service discovery!