Adding metrics server to use host network (#9444)

* Adding metrics server to use host network

* EXternalize value to a variable

inventory/sample/group_vars/k8s_cluster/addons.yml

@@ -18,6 +18,7 @@ metrics_server_enabled: false
 # metrics_server_kubelet_insecure_tls: true
 # metrics_server_metric_resolution: 15s
 # metrics_server_kubelet_preferred_address_types: "InternalIP,ExternalIP,Hostname"
+# metrics_server_host_network: false
 
 # Rancher Local Path Provisioner
 local_path_provisioner_enabled: false

roles/kubernetes-apps/metrics_server/defaults/main.yml

@@ -7,3 +7,4 @@ metrics_server_limits_cpu: 100m
 metrics_server_limits_memory: 200Mi
 metrics_server_requests_cpu: 100m
 metrics_server_requests_memory: 200Mi
+metrics_server_host_network: false

roles/kubernetes-apps/metrics_server/templates/metrics-server-deployment.yaml.j2

@@ -27,6 +27,7 @@ spec:
     spec:
       priorityClassName: system-cluster-critical
       serviceAccountName: metrics-server
+      hostNetwork: {{ metrics_server_host_network | default(false) }}
       containers:
       - name: metrics-server
         image: {{ metrics_server_image_repo }}:{{ metrics_server_image_tag }}