Merge pull request #53146 from brendandburns/ignore

Automatic merge from submit-queue. If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.

Add a label which prevents a node from being added to a cloud load balancer

There are a variety of reasons that you may not want a node in a cluster to participate in a cloud load balancer. For example workload isolation for security, or managing network throughput, or because the node is not in the appropriate virtual network (cluster's that span environments)

This PR adds a label so that you can select which nodes you want to participate.

cmd/kubeadm/app/constants/constants.go

@@ -134,6 +134,10 @@ const (
 	// It's copied over to kubeadm until it's merged in core: https://github.com/kubernetes/kubernetes/pull/39112
 	LabelNodeRoleMaster = "node-role.kubernetes.io/master"
 
+	// LabelNodeRoleExcludeBalancer specifies that the node should be
+	// exclude from load balancers created by a cloud provider.
+	LabelNodeRoleExcludeBalancer = "node.role.kubernetes.io/exclude-balancer"
+
 	// MasterConfigurationConfigMap specifies in what ConfigMap in the kube-system namespace the `kubeadm init` configuration should be stored
 	MasterConfigurationConfigMap = "kubeadm-config"
 

pkg/controller/service/service_controller.go

@@ -598,6 +598,10 @@ func getNodeConditionPredicate() corelisters.NodeConditionPredicate {
 			return false
 		}
 
+		if _, hasExcludeBalancerLabel := node.Labels[constants.LabelNodeRoleExcludeBalancer]; hasExcludeBalancerLabel {
+			return false
+		}
+
 		// If we have no info, don't accept
 		if len(node.Status.Conditions) == 0 {
 			return false