Add support for CAS 1.20 + support for disabling CAS for a given IG

docs/addons.md

@@ -25,7 +25,7 @@ spec:
 Read more in the [official documentation](https://kubernetes-sigs.github.io/aws-load-balancer-controller/latest/).
 
 #### Cluster autoscaler
-{{ kops_feature_table(kops_added_default='1.19', k8s_min='1.15') }}
+{{ kops_feature_table(kops_added_default='1.19') }}
 
 Cluster autoscaler can be enabled to automatically adjust the size of the kubernetes cluster.
 
@@ -41,6 +41,15 @@ spec:
 
 Read more about cluster autoscaler in the [official documentation](https://github.com/kubernetes/autoscaler/tree/master/cluster-autoscaler).
 
+##### Disabling cluster autoscaler for a given instance group
+{{ kops_feature_table(kops_added_default='1.20') }}
+
+You can disable the autoscaler for a given instance group by adding the following to the instance group spec.
+
+```yaml
+spec:
+  autoscale: false
+```
 
 #### Cert-manager
 {{ kops_feature_table(kops_added_default='1.20', k8s_min='1.16') }}

k8s/crds/kops.k8s.io_instancegroups.yaml

@@ -87,6 +87,10 @@ spec:
                 description: AssociatePublicIP is true if we want instances to have
                   a public IP
                 type: boolean
+              autoscale:
+                description: Autoscale determines if autoscaling will be enabled for
+                  the group if cluster autoscaler is enabled
+                type: boolean
               cloudLabels:
                 additionalProperties:
                   type: string

pkg/apis/kops/instancegroup.go

@@ -92,6 +92,8 @@ type InstanceGroupSpec struct {
 	MinSize *int32 `json:"minSize,omitempty"`
 	// MaxSize is the maximum size of the pool
 	MaxSize *int32 `json:"maxSize,omitempty"`
+	// Autoscale determines if autoscaling will be enabled for the group if cluster autoscaler is enabled
+	Autoscale *bool `json:"autoscale,omitempty"`
 	// MachineType is the instance class
 	MachineType string `json:"machineType,omitempty"`
 	// RootVolumeSize is the size of the EBS root volume to use, in GB

pkg/apis/kops/v1alpha2/instancegroup.go

@@ -89,6 +89,8 @@ type InstanceGroupSpec struct {
 	MinSize *int32 `json:"minSize,omitempty"`
 	// MaxSize is the maximum size of the pool
 	MaxSize *int32 `json:"maxSize,omitempty"`
+	// Autoscale determines if autoscaling will be enabled for the group if cluster autoscaler is enabled
+	Autoscale *bool `json:"autoscale,omitempty"`
 	// MachineType is the instance class
 	MachineType string `json:"machineType,omitempty"`
 	// RootVolumeSize is the size of the EBS root volume to use, in GB

pkg/model/components/clusterautoscaler.go

@@ -43,6 +43,8 @@ func (b *ClusterAutoscalerOptionsBuilder) BuildOptions(o interface{}) error {
 		v, err := util.ParseKubernetesVersion(clusterSpec.KubernetesVersion)
 		if err == nil {
 			switch v.Minor {
+			case 20:
+				image = "k8s.gcr.io/autoscaling/cluster-autoscaler:v1.20.0"
 			case 19:
 				image = "k8s.gcr.io/autoscaling/cluster-autoscaler:v1.19.1"
 			case 18:

upup/models/cloudup/resources/addons/cluster-autoscaler.addons.k8s.io/k8s-1.15.yaml.template

@@ -1,5 +1,5 @@
 {{ with .ClusterAutoscaler }}
-# Sourced from https://github.com/kubernetes/autoscaler/tree/master/cluster-autoscaler/cloudprovider/aws/examples
+# Sourced from https://github.com/kubernetes/autoscaler/blob/cluster-autoscaler-release-1.20/cluster-autoscaler/cloudprovider/aws/examples/cluster-autoscaler-multi-asg.yaml
 ---
 apiVersion: v1
 kind: ServiceAccount
@@ -135,7 +135,6 @@ spec:
       labels:
         app: cluster-autoscaler
       annotations:
-        prometheus.io/path: "/metrics"
         prometheus.io/port: "8085"
         prometheus.io/scrape: "true"
     spec:
@@ -158,8 +157,10 @@ spec:
             - --cloud-provider={{ $.CloudProvider }}
             - --expander={{ .Expander }}
             {{ range $name, $spec := GetNodeInstanceGroups }}
+            {{ if WithDefaultBool $spec.Autoscale true }}
             - --nodes={{ $spec.MinSize }}:{{ $spec.MaxSize }}:{{ $name }}.{{ ClusterName }}
             {{ end }}
+            {{ end }}
             - --scale-down-utilization-threshold={{ .ScaleDownUtilizationThreshold }}
             - --skip-nodes-with-local-storage={{ .SkipNodesWithLocalStorage }}
             - --skip-nodes-with-system-pods={{ .SkipNodesWithSystemPods }}