Switch CoreDNS to use the forward plugin instead of proxy

* Use the forward plugin to forward to upstream resolvers, instead
of the proxy plugin. The forward plugin is reported to be a faster
alternative since it can re-use open sockets
* https://coredns.io/explugins/forward/
* https://coredns.io/plugins/proxy/
* https://github.com/kubernetes/kubernetes/issues/73254

CHANGES.md

@@ -6,6 +6,7 @@ Notable changes between versions.
 
 * Update etcd from v3.3.10 to [v3.3.11](https://github.com/etcd-io/etcd/blob/master/CHANGELOG-3.3.md#v3311-2019-1-11)
 * Update CoreDNS from v1.3.0 to [v1.3.1](https://coredns.io/2019/01/13/coredns-1.3.1-release/)
+  * Switch from the `proxy` plugin to the faster `forward` plugin for upsteam resolvers
 * Update Calico from v3.4.0 to [v3.5.0](https://docs.projectcalico.org/v3.5/releases/)
 * Update flannel from v0.10.0 to [v0.11.0](https://github.com/coreos/flannel/releases/tag/v0.11.0)
 * Fix automatic worker deletion on shutdown for cloud platforms

aws/container-linux/kubernetes/bootkube.tf

@@ -1,6 +1,6 @@
 # Self-hosted Kubernetes assets (kubeconfig, manifests)
 module "bootkube" {
-  source = "git::https://github.com/poseidon/terraform-render-bootkube.git?ref=c5bc23ef7a3f5d8e5be976ee60b58dbbfcc3e7c9"
+  source = "git::https://github.com/poseidon/terraform-render-bootkube.git?ref=7dc8f8bf8c1a6bdb9170dd19836520ce436e26d7"
 
   cluster_name          = "${var.cluster_name}"
   api_servers           = ["${format("%s.%s", var.cluster_name, var.dns_zone)}"]

aws/fedora-atomic/kubernetes/bootkube.tf

@@ -1,6 +1,6 @@
 # Self-hosted Kubernetes assets (kubeconfig, manifests)
 module "bootkube" {
-  source = "git::https://github.com/poseidon/terraform-render-bootkube.git?ref=c5bc23ef7a3f5d8e5be976ee60b58dbbfcc3e7c9"
+  source = "git::https://github.com/poseidon/terraform-render-bootkube.git?ref=7dc8f8bf8c1a6bdb9170dd19836520ce436e26d7"
 
   cluster_name          = "${var.cluster_name}"
   api_servers           = ["${format("%s.%s", var.cluster_name, var.dns_zone)}"]

azure/container-linux/kubernetes/bootkube.tf

@@ -1,6 +1,6 @@
 # Self-hosted Kubernetes assets (kubeconfig, manifests)
 module "bootkube" {
-  source = "git::https://github.com/poseidon/terraform-render-bootkube.git?ref=c5bc23ef7a3f5d8e5be976ee60b58dbbfcc3e7c9"
+  source = "git::https://github.com/poseidon/terraform-render-bootkube.git?ref=7dc8f8bf8c1a6bdb9170dd19836520ce436e26d7"
 
   cluster_name          = "${var.cluster_name}"
   api_servers           = ["${format("%s.%s", var.cluster_name, var.dns_zone)}"]

bare-metal/container-linux/kubernetes/bootkube.tf

@@ -1,6 +1,6 @@
 # Self-hosted Kubernetes assets (kubeconfig, manifests)
 module "bootkube" {
-  source = "git::https://github.com/poseidon/terraform-render-bootkube.git?ref=c5bc23ef7a3f5d8e5be976ee60b58dbbfcc3e7c9"
+  source = "git::https://github.com/poseidon/terraform-render-bootkube.git?ref=7dc8f8bf8c1a6bdb9170dd19836520ce436e26d7"
 
   cluster_name                    = "${var.cluster_name}"
   api_servers                     = ["${var.k8s_domain_name}"]

bare-metal/fedora-atomic/kubernetes/bootkube.tf

@@ -1,6 +1,6 @@
 # Self-hosted Kubernetes assets (kubeconfig, manifests)
 module "bootkube" {
-  source = "git::https://github.com/poseidon/terraform-render-bootkube.git?ref=c5bc23ef7a3f5d8e5be976ee60b58dbbfcc3e7c9"
+  source = "git::https://github.com/poseidon/terraform-render-bootkube.git?ref=7dc8f8bf8c1a6bdb9170dd19836520ce436e26d7"
 
   cluster_name          = "${var.cluster_name}"
   api_servers           = ["${var.k8s_domain_name}"]

digital-ocean/container-linux/kubernetes/bootkube.tf

@@ -1,6 +1,6 @@
 # Self-hosted Kubernetes assets (kubeconfig, manifests)
 module "bootkube" {
-  source = "git::https://github.com/poseidon/terraform-render-bootkube.git?ref=c5bc23ef7a3f5d8e5be976ee60b58dbbfcc3e7c9"
+  source = "git::https://github.com/poseidon/terraform-render-bootkube.git?ref=7dc8f8bf8c1a6bdb9170dd19836520ce436e26d7"
 
   cluster_name          = "${var.cluster_name}"
   api_servers           = ["${format("%s.%s", var.cluster_name, var.dns_zone)}"]

digital-ocean/fedora-atomic/kubernetes/bootkube.tf

@@ -1,6 +1,6 @@
 # Self-hosted Kubernetes assets (kubeconfig, manifests)
 module "bootkube" {
-  source = "git::https://github.com/poseidon/terraform-render-bootkube.git?ref=c5bc23ef7a3f5d8e5be976ee60b58dbbfcc3e7c9"
+  source = "git::https://github.com/poseidon/terraform-render-bootkube.git?ref=7dc8f8bf8c1a6bdb9170dd19836520ce436e26d7"
 
   cluster_name          = "${var.cluster_name}"
   api_servers           = ["${format("%s.%s", var.cluster_name, var.dns_zone)}"]

google-cloud/container-linux/kubernetes/bootkube.tf

@@ -1,6 +1,6 @@
 # Self-hosted Kubernetes assets (kubeconfig, manifests)
 module "bootkube" {
-  source = "git::https://github.com/poseidon/terraform-render-bootkube.git?ref=c5bc23ef7a3f5d8e5be976ee60b58dbbfcc3e7c9"
+  source = "git::https://github.com/poseidon/terraform-render-bootkube.git?ref=7dc8f8bf8c1a6bdb9170dd19836520ce436e26d7"
 
   cluster_name          = "${var.cluster_name}"
   api_servers           = ["${format("%s.%s", var.cluster_name, var.dns_zone)}"]

google-cloud/fedora-atomic/kubernetes/bootkube.tf

@@ -1,6 +1,6 @@
 # Self-hosted Kubernetes assets (kubeconfig, manifests)
 module "bootkube" {
-  source = "git::https://github.com/poseidon/terraform-render-bootkube.git?ref=c5bc23ef7a3f5d8e5be976ee60b58dbbfcc3e7c9"
+  source = "git::https://github.com/poseidon/terraform-render-bootkube.git?ref=7dc8f8bf8c1a6bdb9170dd19836520ce436e26d7"
 
   cluster_name          = "${var.cluster_name}"
   api_servers           = ["${format("%s.%s", var.cluster_name, var.dns_zone)}"]