machine controller: improve EC2 state handling

Signed-off-by: Naadir Jeewa <[email protected]>

Author: Naadir Jeewa

controllers/awsmachine_controller.go

@@ -189,23 +189,23 @@ func (r *AWSMachineReconciler) reconcileDelete(machineScope *scope.MachineScope,
 		// and AWSMachine
 		// 3. Issue a delete
 		// 4. Scale controller deployment to 1
-		machineScope.V(2).Info("Unable to locate instance by ID or tags")
+		machineScope.V(2).Info("Unable to locate EC2 instance by ID or tags")
 		r.Recorder.Eventf(machineScope.AWSMachine, corev1.EventTypeWarning, "NoInstanceFound", "Unable to find matching EC2 instance")
 		machineScope.AWSMachine.Finalizers = util.Filter(machineScope.AWSMachine.Finalizers, infrav1.MachineFinalizer)
 		return reconcile.Result{}, nil
 	}
 
-	machineScope.V(3).Info("Instance found matching deleted AWSMachine", "instanceID", instance.ID)
+	machineScope.V(3).Info("EC2 instance found matching deleted AWSMachine", "instance-id", instance.ID)
 
 	// Check the instance state. If it's already shutting down or terminated,
 	// do nothing. Otherwise attempt to delete it.
 	// This decision is based on the ec2-instance-lifecycle graph at
 	// https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/ec2-instance-lifecycle.html
 	switch instance.State {
 	case infrav1.InstanceStateShuttingDown, infrav1.InstanceStateTerminated:
-		machineScope.Info("Instance is shutting down or already terminated", "instanceID", instance.ID)
+		machineScope.Info("EC2 instance is shutting down or already terminated", "instance-id", instance.ID)
 	default:
-		machineScope.Info("Terminating instance", "instanceID", instance.ID)
+		machineScope.Info("Terminating EC2 instance", "instance-id", instance.ID)
 		if err := ec2Service.TerminateInstanceAndWait(instance.ID); err != nil {
 			r.Recorder.Eventf(machineScope.AWSMachine, corev1.EventTypeWarning, "FailedTerminate", "Failed to terminate instance %q: %v", instance.ID, err)
 			return reconcile.Result{}, errors.Wrap(err, "failed to terminate instance")
@@ -231,6 +231,7 @@ func (r *AWSMachineReconciler) reconcileDelete(machineScope *scope.MachineScope,
 			}
 		}
 
+		machineScope.Info("EC2 instance successfully terminated", "instance-id", instance.ID)
 		r.Recorder.Eventf(machineScope.AWSMachine, corev1.EventTypeNormal, "SuccessfulTerminate", "Terminated instance %q", instance.ID)
 	}
 
@@ -276,6 +277,7 @@ func (r *AWSMachineReconciler) reconcileNormal(ctx context.Context, machineScope
 
 	// If the AWSMachine doesn't have our finalizer, add it.
 	if !util.Contains(machineScope.AWSMachine.Finalizers, infrav1.MachineFinalizer) {
+		machineScope.V(1).Info("Adding Cluster API Provider AWS finalizer")
 		machineScope.AWSMachine.Finalizers = append(machineScope.AWSMachine.Finalizers, infrav1.MachineFinalizer)
 	}
 
@@ -300,6 +302,7 @@ func (r *AWSMachineReconciler) reconcileNormal(ctx context.Context, machineScope
 
 	// Set an error message if we couldn't find the instance.
 	if instance == nil {
+		machineScope.Info("EC2 instance cannot be found")
 		machineScope.SetErrorReason(capierrors.UpdateMachineError)
 		machineScope.SetErrorMessage(errors.New("EC2 instance cannot be found"))
 		return reconcile.Result{}, nil
@@ -308,26 +311,42 @@ func (r *AWSMachineReconciler) reconcileNormal(ctx context.Context, machineScope
 	// TODO(ncdc): move this validation logic into a validating webhook
 	if errs := r.validateUpdate(&machineScope.AWSMachine.Spec, instance); len(errs) > 0 {
 		agg := kerrors.NewAggregate(errs)
+		machineScope.Info("Invalid update", "failedUpdates", agg.Error())
 		r.Recorder.Eventf(machineScope.AWSMachine, corev1.EventTypeWarning, "InvalidUpdate", "Invalid update: %s", agg.Error())
 		return reconcile.Result{}, nil
 	}
 
 	// Make sure Spec.ProviderID is always set.
 	machineScope.SetProviderID(fmt.Sprintf("aws:////%s", instance.ID))
 
-	// Proceed to reconcile the AWSMachine state.
+	// See https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/ec2-instance-lifecycle.html
+
+	existingInstanceState := machineScope.GetInstanceState()
 	machineScope.SetInstanceState(instance.State)
 
-	// TODO(vincepri): Remove this annotation when clusterctl is no longer relevant.
-	machineScope.SetAnnotation("cluster-api-provider-aws", "true")
+	// Proceed to reconcile the AWSMachine state.
+	if existingInstanceState == nil || *existingInstanceState != instance.State {
+		machineScope.Info("EC2 instance state changed", "state", instance.State, "instance-id", *machineScope.GetInstanceID())
+	}
 
 	switch instance.State {
+	case infrav1.InstanceStatePending, infrav1.InstanceStateStopping, infrav1.InstanceStateStopped:
+		machineScope.SetNotReady()
 	case infrav1.InstanceStateRunning:
-		machineScope.Info("Machine instance is running", "instance-id", *machineScope.GetInstanceID())
 		machineScope.SetReady()
-	case infrav1.InstanceStatePending:
-		machineScope.Info("Machine instance is pending", "instance-id", *machineScope.GetInstanceID())
+	case infrav1.InstanceStateShuttingDown, infrav1.InstanceStateTerminated:
+		machineScope.SetNotReady()
+		machineScope.Info("Unexpected EC2 instance termination", "state", instance.State, "instance-id", *machineScope.GetInstanceID())
+		r.Recorder.Eventf(machineScope.AWSMachine, corev1.EventTypeWarning, "InstanceUnexpectedTermination", "Unexpected EC2 instance termination")
 	default:
+		machineScope.SetNotReady()
+		machineScope.Info("EC2 instance state is undefined", "state", instance.State, "instance-id", *machineScope.GetInstanceID())
+		r.Recorder.Eventf(machineScope.AWSMachine, corev1.EventTypeWarning, "InstanceUnhandledState", "EC2 instance state is undefined")
+		machineScope.SetErrorReason(capierrors.UpdateMachineError)
+		machineScope.SetErrorMessage(errors.Errorf("EC2 instance state %q is undefined", instance.State))
+	}
+
+	if instance.State == infrav1.InstanceStateTerminated {
 		machineScope.SetErrorReason(capierrors.UpdateMachineError)
 		machineScope.SetErrorMessage(errors.Errorf("EC2 instance state %q is unexpected", instance.State))
 	}
@@ -336,6 +355,9 @@ func (r *AWSMachineReconciler) reconcileNormal(ctx context.Context, machineScope
 		return reconcile.Result{}, errors.Errorf("failed to reconcile LB attachment: %+v", err)
 	}
 
+	// TODO(vincepri): Remove this annotation when clusterctl is no longer relevant.
+	machineScope.SetAnnotation("cluster-api-provider-aws", "true")
+
 	existingSecurityGroups, err := ec2svc.GetInstanceSecurityGroups(*machineScope.GetInstanceID())
 	if err != nil {
 		return reconcile.Result{}, err
@@ -363,10 +385,11 @@ func (r *AWSMachineReconciler) getOrCreate(scope *scope.MachineScope, ec2svc ser
 	}
 
 	if instance == nil {
+		scope.Info("Creating EC2 instance")
 		// Create a new AWSMachine instance if we couldn't find a running instance.
 		instance, err = ec2svc.CreateInstance(scope)
 		if err != nil {
-			return nil, errors.Wrapf(err, "failed to create AWSMachine instance")
+			return nil, errors.Wrapf(err, "failed to create EC2 instance")
 		}
 	}
 
@@ -390,14 +413,21 @@ func (r *AWSMachineReconciler) reconcileLBAttachment(machineScope *scope.Machine
 // validateUpdate checks that no immutable fields have been updated and
 // returns a slice of errors representing attempts to change immutable state.
 func (r *AWSMachineReconciler) validateUpdate(spec *infrav1.AWSMachineSpec, i *infrav1.Instance) (errs []error) {
+
+	// EC2 instance attributes start disapearing during shutdown and termination, so do not
+	// perform more checks
+	if i.State == infrav1.InstanceStateTerminated || i.State == infrav1.InstanceStateShuttingDown {
+		return nil
+	}
+
 	// Instance Type
 	if spec.InstanceType != i.Type {
-		errs = append(errs, errors.Errorf("instance type cannot be mutated from %q to %q", i.Type, spec.InstanceType))
+		errs = append(errs, errors.Errorf("EC2 instance type cannot be mutated from %q to %q", i.Type, spec.InstanceType))
 	}
 
 	// IAM Profile
 	if spec.IAMInstanceProfile != i.IAMProfile {
-		errs = append(errs, errors.Errorf("instance IAM profile cannot be mutated from %q to %q", i.IAMProfile, spec.IAMInstanceProfile))
+		errs = append(errs, errors.Errorf("EC2 instance IAM profile cannot be mutated from %q to %q", i.IAMProfile, spec.IAMInstanceProfile))
 	}
 
 	// SSH Key Name (also account for default)

controllers/awsmachine_controller_test.go

@@ -219,26 +219,35 @@ var _ = Describe("AWSMachineReconciler", func() {
 						klog.SetOutput(buf)
 					})
 
-					It("should set instance to running", func() {
-						instance.State = infrav1.InstanceStateRunning
-						_, _ = reconciler.reconcileNormal(context.Background(), ms, cs)
-						Expect(ms.AWSMachine.Status.InstanceState).To(PointTo(Equal(infrav1.InstanceStateRunning)))
-						Expect(buf.String()).To(ContainSubstring(("Machine instance is running")))
-					})
-
 					It("should set instance to pending", func() {
 						instance.State = infrav1.InstanceStatePending
 						_, _ = reconciler.reconcileNormal(context.Background(), ms, cs)
 						Expect(ms.AWSMachine.Status.InstanceState).To(PointTo(Equal(infrav1.InstanceStatePending)))
-						Expect(buf.String()).To(ContainSubstring(("Machine instance is pending")))
+						Expect(ms.AWSMachine.Status.Ready).To(Equal(false))
+						Expect(buf.String()).To(ContainSubstring(("EC2 instance state changed")))
+					})
+
+					It("should set instance to running", func() {
+						instance.State = infrav1.InstanceStateRunning
+						_, _ = reconciler.reconcileNormal(context.Background(), ms, cs)
+						Expect(ms.AWSMachine.Status.InstanceState).To(PointTo(Equal(infrav1.InstanceStateRunning)))
+						Expect(ms.AWSMachine.Status.Ready).To(Equal(true))
+						Expect(buf.String()).To(ContainSubstring(("EC2 instance state changed")))
 					})
 				})
+			})
 
-				It("should set error message when instance status unknown", func() {
-					instance.State = infrav1.InstanceStateStopping
+			Context("New EC2 instance state", func() {
+				It("should error when the instance state is a new unseen one", func() {
+					buf := new(bytes.Buffer)
+					klog.SetOutput(buf)
+					ec2Svc.EXPECT().GetInstanceSecurityGroups(gomock.Any()).Return(nil, errors.New("stop here"))
+					instance.State = "NewAWSMachineState"
 					_, _ = reconciler.reconcileNormal(context.Background(), ms, cs)
-					Expect(ms.AWSMachine.Status.ErrorReason).To(PointTo(Equal(capierrors.UpdateMachineError)))
-					Expect(ms.AWSMachine.Status.ErrorMessage).To(PointTo(Equal("EC2 instance state \"stopping\" is unexpected")))
+					Expect(ms.AWSMachine.Status.Ready).To(Equal(false))
+					Expect(buf.String()).To(ContainSubstring(("EC2 instance state is undefined")))
+					Expect(recorder.Events).To(Receive(ContainSubstring("InstanceUnhandledState")))
+					Expect(ms.AWSMachine.Status.ErrorMessage).To(PointTo(Equal("EC2 instance state \"NewAWSMachineState\" is undefined")))
 				})
 			})
 
@@ -284,6 +293,71 @@ var _ = Describe("AWSMachineReconciler", func() {
 					Expect(err).To(BeNil())
 				})
 			})
+
+			When("temporarily stopping then starting the AWSMachine", func() {
+				var buf *bytes.Buffer
+				BeforeEach(func() {
+					buf = new(bytes.Buffer)
+					klog.SetOutput(buf)
+					ec2Svc.EXPECT().GetInstanceSecurityGroups(gomock.Any()).
+						Return(map[string][]string{"eid": {}}, nil).AnyTimes()
+					ec2Svc.EXPECT().GetCoreSecurityGroups(gomock.Any()).Return([]string{}, nil).AnyTimes()
+				})
+
+				It("should set instance to stopping and unready", func() {
+					instance.State = infrav1.InstanceStateStopping
+					_, _ = reconciler.reconcileNormal(context.Background(), ms, cs)
+					Expect(ms.AWSMachine.Status.InstanceState).To(PointTo(Equal(infrav1.InstanceStateStopping)))
+					Expect(ms.AWSMachine.Status.Ready).To(Equal(false))
+					Expect(buf.String()).To(ContainSubstring(("EC2 instance state changed")))
+				})
+
+				It("should then set instance to stopped and unready", func() {
+					instance.State = infrav1.InstanceStateStopped
+					_, _ = reconciler.reconcileNormal(context.Background(), ms, cs)
+					Expect(ms.AWSMachine.Status.InstanceState).To(PointTo(Equal(infrav1.InstanceStateStopped)))
+					Expect(ms.AWSMachine.Status.Ready).To(Equal(false))
+					Expect(buf.String()).To(ContainSubstring(("EC2 instance state changed")))
+				})
+
+				It("should then set instance to running and ready once it is restarted", func() {
+					instance.State = infrav1.InstanceStateRunning
+					_, _ = reconciler.reconcileNormal(context.Background(), ms, cs)
+					Expect(ms.AWSMachine.Status.InstanceState).To(PointTo(Equal(infrav1.InstanceStateRunning)))
+					Expect(ms.AWSMachine.Status.Ready).To(Equal(true))
+					Expect(buf.String()).To(ContainSubstring(("EC2 instance state changed")))
+				})
+			})
+
+			When("deleting the AWSMachine outside of Kubernetes", func() {
+				var buf *bytes.Buffer
+				BeforeEach(func() {
+					buf = new(bytes.Buffer)
+					klog.SetOutput(buf)
+					ec2Svc.EXPECT().GetInstanceSecurityGroups(gomock.Any()).
+						Return(map[string][]string{"eid": {}}, nil).AnyTimes()
+					ec2Svc.EXPECT().GetCoreSecurityGroups(gomock.Any()).Return([]string{}, nil).AnyTimes()
+				})
+
+				It("should warn if an instance is shutting-down", func() {
+					instance.State = infrav1.InstanceStateShuttingDown
+					_, _ = reconciler.reconcileNormal(context.Background(), ms, cs)
+					Expect(ms.AWSMachine.Status.Ready).To(Equal(false))
+					Expect(buf.String()).To(ContainSubstring(("Unexpected EC2 instance termination")))
+					Expect(recorder.Events).To(Receive(ContainSubstring("UnexpectedTermination")))
+				})
+
+				It("should error when the instance is seen as terminated", func() {
+					instance.State = infrav1.InstanceStateTerminated
+					_, _ = reconciler.reconcileNormal(context.Background(), ms, cs)
+					Expect(ms.AWSMachine.Status.Ready).To(Equal(false))
+					Expect(buf.String()).To(ContainSubstring(("Unexpected EC2 instance termination")))
+					Expect(recorder.Events).To(Receive(ContainSubstring("UnexpectedTermination")))
+					Expect(ms.AWSMachine.Status.ErrorMessage).To(PointTo(Equal("EC2 instance state \"terminated\" is unexpected")))
+				})
+
+			})
+
 		})
 	})
 
@@ -312,7 +386,7 @@ var _ = Describe("AWSMachineReconciler", func() {
 
 			_, err := reconciler.reconcileDelete(ms, cs)
 			Expect(err).To(BeNil())
-			Expect(buf.String()).To(ContainSubstring("Unable to locate instance by ID or tags"))
+			Expect(buf.String()).To(ContainSubstring("Unable to locate EC2 instance by ID or tags"))
 			Expect(ms.AWSMachine.Finalizers).To(ConsistOf(metav1.FinalizerDeleteDependents))
 			Expect(recorder.Events).To(Receive(ContainSubstring("NoInstanceFound")))
 		})
@@ -327,7 +401,7 @@ var _ = Describe("AWSMachineReconciler", func() {
 
 			_, err := reconciler.reconcileDelete(ms, cs)
 			Expect(err).To(BeNil())
-			Expect(buf.String()).To(ContainSubstring("Instance is shutting down or already terminated"))
+			Expect(buf.String()).To(ContainSubstring("EC2 instance is shutting down or already terminated"))
 			Expect(ms.AWSMachine.Finalizers).To(ConsistOf(metav1.FinalizerDeleteDependents))
 		})
 
@@ -341,7 +415,7 @@ var _ = Describe("AWSMachineReconciler", func() {
 
 			_, err := reconciler.reconcileDelete(ms, cs)
 			Expect(err).To(BeNil())
-			Expect(buf.String()).To(ContainSubstring("Instance is shutting down or already terminated"))
+			Expect(buf.String()).To(ContainSubstring("EC2 instance is shutting down or already terminated"))
 			Expect(ms.AWSMachine.Finalizers).To(ConsistOf(metav1.FinalizerDeleteDependents))
 		})
 
@@ -361,7 +435,7 @@ var _ = Describe("AWSMachineReconciler", func() {
 
 				_, err := reconciler.reconcileDelete(ms, cs)
 				Expect(errors.Cause(err)).To(MatchError(expected))
-				Expect(buf.String()).To(ContainSubstring("Terminating instance"))
+				Expect(buf.String()).To(ContainSubstring("Terminating EC2 instance"))
 				Expect(recorder.Events).To(Receive(ContainSubstring("FailedTerminate")))
 			})
 
@@ -414,7 +488,6 @@ var _ = Describe("AWSMachineReconciler", func() {
 				})
 			})
 		})
-
 	})
 })
 

pkg/cloud/scope/machine.go

@@ -154,6 +154,11 @@ func (m *MachineScope) SetReady() {
 	m.AWSMachine.Status.Ready = true
 }
 
+// SetNotReady sets the AWSMachine Ready Status to false
+func (m *MachineScope) SetNotReady() {
+	m.AWSMachine.Status.Ready = false
+}
+
 // SetErrorMessage sets the AWSMachine status error message.
 func (m *MachineScope) SetErrorMessage(v error) {
 	m.AWSMachine.Status.ErrorMessage = pointer.StringPtr(v.Error())