Merge pull request #8206 from rifelpet/automated-cherry-pick-of-#8176…

…-origin-release-1.17

Automated cherry pick of #8176 and #8209: Add deprecation warning for older k8s versions

permalinks/upgrade_k8s.md

@@ -1,5 +1,11 @@
 # Kubernetes Upgrade Recommended
 
+Kops has established a deprecation policy for Kubernetes version support.
+Kops 1.18 will drop support for Kubernetes 1.8 and below.
+
+
 You are running a version of kubernetes that we recommend upgrading.
 
 Please see the [instructions for how to upgrade kubernetes](https://kops.sigs.k8s.io/operations/updates_and_upgrades/#upgrading-kubernetes)
+
+Please see the deprecation policy [GitHub issue](https://github.com/kubernetes/kops/issues/7999) for more information and to leave feedback.

upup/pkg/fi/cloudup/apply_cluster.go

@@ -91,6 +91,8 @@ var (
 	AlphaAllowALI = featureflag.New("AlphaAllowALI", featureflag.Bool(false))
 	// CloudupModels a list of supported models
 	CloudupModels = []string{"proto", "cloudup"}
+	// OldestSupportedKubernetesVersion is the oldest kubernetes version that is supported in Kops
+	OldestSupportedKubernetesVersion = "1.9.0"
 )
 
 type ApplyClusterCmd struct {
@@ -1044,6 +1046,20 @@ func (c *ApplyClusterCmd) validateKubernetesVersion() error {
 		return nil
 	}
 
+	if !util.IsKubernetesGTE(OldestSupportedKubernetesVersion, *parsed) {
+		fmt.Printf("\n")
+		fmt.Printf(starline)
+		fmt.Printf("\n")
+		fmt.Printf("Kops support for this Kubernetes version is deprecated and will be removed in a future release.\n")
+		fmt.Printf("\n")
+		fmt.Printf("Upgrading is recommended\n")
+		fmt.Printf("More information: %s\n", buildPermalink("upgrade_k8s", ""))
+		fmt.Printf("\n")
+		fmt.Printf(starline)
+		fmt.Printf("\n")
+
+	}
+
 	// TODO: make util.ParseKubernetesVersion not return a pointer
 	kubernetesVersion := *parsed