Use node affinity to schedule pods on supported platforms

CHANGELOG.md

@@ -13,6 +13,9 @@
   Operation cannot be fulfilled on oneagents.dynatrace.com \"oneagent\": the object has been modified; please apply your changes to the latest version and try again
   ```
 
+### Other changes
+* Support deprecation of `beta.kubernetes.io/arch` and `beta.kubernetes.io/os` labels ([#199](https://github.com/Dynatrace/dynatrace-oneagent-operator/pull/199))
+
 ## v0.6
 
 ### Features

deploy/kubernetes.yaml

@@ -582,9 +582,28 @@ spec:
             limits:
               cpu: 100m
               memory: 256Mi
-      nodeSelector:
-        beta.kubernetes.io/os: linux
-        beta.kubernetes.io/arch: amd64
+      affinity:
+        nodeAffinity:
+          requiredDuringSchedulingIgnoredDuringExecution:
+            nodeSelectorTerms:
+              - matchExpressions:
+                  - key: beta.kubernetes.io/arch
+                    operator: In
+                    values:
+                      - amd64
+                  - key: beta.kubernetes.io/os
+                    operator: In
+                    values:
+                      - linux
+              - matchExpressions:
+                  - key: kubernetes.io/arch
+                    operator: In
+                    values:
+                      - amd64
+                  - key: kubernetes.io/os
+                    operator: In
+                    values:
+                      - linux
       serviceAccountName: dynatrace-oneagent-operator
 ---
 apiVersion: rbac.authorization.k8s.io/v1beta1

deploy/kubernetes/deployment.yaml

@@ -44,7 +44,26 @@ spec:
             limits:
               cpu: 100m
               memory: 256Mi
-      nodeSelector:
-        beta.kubernetes.io/os: linux
-        beta.kubernetes.io/arch: amd64
+      affinity:
+        nodeAffinity:
+          requiredDuringSchedulingIgnoredDuringExecution:
+            nodeSelectorTerms:
+              - matchExpressions:
+                  - key: beta.kubernetes.io/arch
+                    operator: In
+                    values:
+                      - amd64
+                  - key: beta.kubernetes.io/os
+                    operator: In
+                    values:
+                      - linux
+              - matchExpressions:
+                  - key: kubernetes.io/arch
+                    operator: In
+                    values:
+                      - amd64
+                  - key: kubernetes.io/os
+                    operator: In
+                    values:
+                      - linux
       serviceAccountName: dynatrace-oneagent-operator

deploy/openshift.yaml

@@ -522,9 +522,28 @@ spec:
             limits:
               cpu: 100m
               memory: 256Mi
-      nodeSelector:
-        beta.kubernetes.io/os: linux
-        beta.kubernetes.io/arch: amd64
+      affinity:
+        nodeAffinity:
+          requiredDuringSchedulingIgnoredDuringExecution:
+            nodeSelectorTerms:
+              - matchExpressions:
+                  - key: beta.kubernetes.io/arch
+                    operator: In
+                    values:
+                      - amd64
+                  - key: beta.kubernetes.io/os
+                    operator: In
+                    values:
+                      - linux
+              - matchExpressions:
+                  - key: kubernetes.io/arch
+                    operator: In
+                    values:
+                      - amd64
+                  - key: kubernetes.io/os
+                    operator: In
+                    values:
+                      - linux
       serviceAccountName: dynatrace-oneagent-operator
 ---
 apiVersion: rbac.authorization.k8s.io/v1beta1

deploy/openshift/deployment.yaml

@@ -44,7 +44,26 @@ spec:
             limits:
               cpu: 100m
               memory: 256Mi
-      nodeSelector:
-        beta.kubernetes.io/os: linux
-        beta.kubernetes.io/arch: amd64
+      affinity:
+        nodeAffinity:
+          requiredDuringSchedulingIgnoredDuringExecution:
+            nodeSelectorTerms:
+              - matchExpressions:
+                  - key: beta.kubernetes.io/arch
+                    operator: In
+                    values:
+                      - amd64
+                  - key: beta.kubernetes.io/os
+                    operator: In
+                    values:
+                      - linux
+              - matchExpressions:
+                  - key: kubernetes.io/arch
+                    operator: In
+                    values:
+                      - amd64
+                  - key: kubernetes.io/os
+                    operator: In
+                    values:
+                      - linux
       serviceAccountName: dynatrace-oneagent-operator

pkg/apis/dynatrace/v1alpha1/defaults.go

@@ -17,13 +17,6 @@ func SetDefaults_OneAgentSpec(obj *OneAgentSpec) {
 		obj.Image = "docker.io/dynatrace/oneagent:latest"
 	}
 
-	if _, ok := obj.NodeSelector["beta.kubernetes.io/os"]; !ok {
-		if obj.NodeSelector == nil {
-			obj.NodeSelector = make(map[string]string)
-		}
-		obj.NodeSelector["beta.kubernetes.io/os"] = "linux"
-	}
-
 	if obj.ServiceAccountName == "" {
 		obj.ServiceAccountName = "dynatrace-oneagent"
 	}

pkg/apis/dynatrace/v1alpha1/defaults_test.go

@@ -11,7 +11,6 @@ func TestSetDefaults_OneAgentSpec(t *testing.T) {
 	SetDefaults_OneAgentSpec(oa)
 	assert.NotNil(t, oa.WaitReadySeconds)
 	assert.NotEmpty(t, oa.Image)
-	assert.NotEmpty(t, oa.NodeSelector)
 	assert.NotEmpty(t, oa.Env)
 }
 

pkg/controller/oneagent/oneagent_controller.go

@@ -211,8 +211,8 @@ func (r *ReconcileOneAgent) Reconcile(request reconcile.Request) (reconcile.Resu
 	}
 
 	// finally we have to determine the correct non error phase
-	updateCR, err = r.determineOneAgentPhase(instance);
-	if (updateCR) {
+	updateCR, err = r.determineOneAgentPhase(instance)
+	if updateCR {
 		logger.Info("updating custom resource", "cause", "phase change")
 		if errClient := r.updateCR(instance); errClient != nil {
 			if err != nil {
@@ -222,7 +222,6 @@ func (r *ReconcileOneAgent) Reconcile(request reconcile.Request) (reconcile.Resu
 		}
 	}
 
-
 	return reconcile.Result{RequeueAfter: 30 * time.Minute}, nil
 }
 
@@ -397,6 +396,9 @@ func newDaemonSetForCR(instance *dynatracev1alpha1.OneAgent) *appsv1.DaemonSet {
 func newPodSpecForCR(instance *dynatracev1alpha1.OneAgent) corev1.PodSpec {
 	trueVar := true
 
+	// K8s 1.18+ is expected to drop the "beta.kubernetes.io" labels in favor of "kubernetes.io" which was added on K8s 1.14.
+	// To support both older and newer K8s versions we use node affinity.
+
 	return corev1.PodSpec{
 		Containers: []corev1.Container{{
 			Args:            instance.Spec.Args,
@@ -433,6 +435,42 @@ func newPodSpecForCR(instance *dynatracev1alpha1.OneAgent) corev1.PodSpec {
 		ServiceAccountName: instance.Spec.ServiceAccountName,
 		Tolerations:        instance.Spec.Tolerations,
 		DNSPolicy:          instance.Spec.DNSPolicy,
+		Affinity: &corev1.Affinity{
+			NodeAffinity: &corev1.NodeAffinity{
+				RequiredDuringSchedulingIgnoredDuringExecution: &corev1.NodeSelector{
+					NodeSelectorTerms: []corev1.NodeSelectorTerm{
+						corev1.NodeSelectorTerm{
+							MatchExpressions: []corev1.NodeSelectorRequirement{
+								corev1.NodeSelectorRequirement{
+									Key:      "beta.kubernetes.io/arch",
+									Operator: corev1.NodeSelectorOpIn,
+									Values:   []string{"amd64"},
+								},
+								corev1.NodeSelectorRequirement{
+									Key:      "beta.kubernetes.io/os",
+									Operator: corev1.NodeSelectorOpIn,
+									Values:   []string{"linux"},
+								},
+							},
+						},
+						corev1.NodeSelectorTerm{
+							MatchExpressions: []corev1.NodeSelectorRequirement{
+								corev1.NodeSelectorRequirement{
+									Key:      "kubernetes.io/arch",
+									Operator: corev1.NodeSelectorOpIn,
+									Values:   []string{"amd64"},
+								},
+								corev1.NodeSelectorRequirement{
+									Key:      "kubernetes.io/os",
+									Operator: corev1.NodeSelectorOpIn,
+									Values:   []string{"linux"},
+								},
+							},
+						},
+					},
+				},
+			},
+		},
 		Volumes: []corev1.Volume{{
 			Name: "host-root",
 			VolumeSource: corev1.VolumeSource{