diff --git a/Makefile b/Makefile
index 8db4c7e2..9a33d483 100644
--- a/Makefile
+++ b/Makefile
@@ -68,6 +68,10 @@ test-debug: envtest ginkgo
 test-update: envtest ginkgo
 	KUBEBUILDER_ASSETS="$(shell $(ENVTEST) use $(ENVTEST_K8S_VERSION) -p path)" UPDATE_TESTCASES=true $(GINKGO) -r --fail-fast 
 
+.PHONY: test-tortoisectl
+test-tortoisectl: envtest
+	KUBEBUILDER_ASSETS="$(shell $(ENVTEST) use $(ENVTEST_K8S_VERSION) -p path)"	go test -timeout 30s -run Test_TortoiseCtlStop ./cmd/tortoisectl/test/... --update
+
 GINKGO ?= $(LOCALBIN)/ginkgo
 GINKGO_VERSION ?= v2.1.4
 
@@ -82,6 +86,10 @@ $(GINKGO): $(LOCALBIN)
 build: generate fmt vet ## Build manager binary.
 	go build -o bin/manager main.go
 
+.PHONY: build-tortoisectl
+build-tortoisectl:
+	go build -o bin/tortoisectl cmd/tortoisectl/main.go
+
 .PHONY: run
 run: manifests generate fmt vet ## Run a controller from your host.
 	go run ./main.go
diff --git a/api/core/v1/pod_webhook.go b/api/core/v1/pod_webhook.go
index 8b337af3..0affe213 100644
--- a/api/core/v1/pod_webhook.go
+++ b/api/core/v1/pod_webhook.go
@@ -118,7 +118,7 @@ func (h *PodWebhook) Default(ctx context.Context, obj runtime.Object) error {
 		return nil
 	}
 
-	h.podService.ModifyPodResource(pod, tortoise)
+	h.podService.ModifyPodSpecResource(&pod.Spec, tortoise)
 	pod.Annotations[annotation.PodMutationAnnotation] = fmt.Sprintf("this pod is mutated by tortoise (%s)", tortoise.Name)
 
 	return nil
diff --git a/cmd/tortoisectl/commands/root.go b/cmd/tortoisectl/commands/root.go
new file mode 100644
index 00000000..29d693f1
--- /dev/null
+++ b/cmd/tortoisectl/commands/root.go
@@ -0,0 +1,21 @@
+package commands
+
+import (
+	"fmt"
+	"os"
+
+	"github.com/spf13/cobra"
+)
+
+var rootCmd = &cobra.Command{
+	Use:   "tortoisectl [COMMANDS]",
+	Short: "tortoisectl is a CLI for managing Tortoise",
+	Long:  `tortoisectl is a CLI for managing Tortoise.`,
+}
+
+func Execute() {
+	if err := rootCmd.Execute(); err != nil {
+		fmt.Fprintln(os.Stderr, err)
+		os.Exit(1)
+	}
+}
diff --git a/cmd/tortoisectl/commands/stop.go b/cmd/tortoisectl/commands/stop.go
new file mode 100644
index 00000000..0996533b
--- /dev/null
+++ b/cmd/tortoisectl/commands/stop.go
@@ -0,0 +1,91 @@
+package commands
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+
+	"github.com/mercari/tortoise/pkg/deployment"
+	"github.com/mercari/tortoise/pkg/pod"
+	"github.com/mercari/tortoise/pkg/stoper"
+	"github.com/spf13/cobra"
+	"k8s.io/client-go/tools/clientcmd"
+	"k8s.io/client-go/util/homedir"
+	"sigs.k8s.io/controller-runtime/pkg/client"
+)
+
+var stopCmd = &cobra.Command{
+	Use:   "stop tortoise1 tortoise2...",
+	Short: "stop tortoise(s) safely",
+	Long:  `stop is the command to turn off tortoise(s) safely.`,
+	RunE: func(cmd *cobra.Command, args []string) error {
+		// validation
+		if !stopAll {
+			if len(args) != 0 {
+				return fmt.Errorf("tortoise name shouldn't be specified because of --all flag")
+			}
+		} else {
+			if stopNamespace == "" {
+				return fmt.Errorf("namespace must be specified")
+			}
+			if len(args) == 0 {
+				return fmt.Errorf("tortoise name must be specified")
+			}
+		}
+
+		config, err := clientcmd.BuildConfigFromFlags("", kubeconfig)
+		if err != nil {
+			return fmt.Errorf("failed to build config: %v", err)
+		}
+
+		client, err := client.New(config, client.Options{})
+		if err != nil {
+			return fmt.Errorf("failed to create client: %v", err)
+		}
+
+		deploymentService := deployment.New(client, "", "", nil)
+		podService, err := pod.New(map[string]int64{}, "", nil, nil)
+		if err != nil {
+			return fmt.Errorf("failed to create pod service: %v", err)
+		}
+
+		stoperService := stoper.New(client, deploymentService, podService)
+
+		err = stoperService.Stop(cmd.Context(), args, stopNamespace, stopAll, os.Stdout, stoper.NoLoweringResource)
+		if err != nil {
+			return fmt.Errorf("failed to stop tortoise(s): %v", err)
+		}
+
+		return nil
+	},
+}
+
+var (
+	// namespace to stop tortoise(s) in
+	stopNamespace string
+	// stop all tortoises in the specified namespace, or in all namespaces if no namespace is specified.
+	stopAll bool
+	// Stop tortoise without lowering resource requests.
+	// If this flag is specified and the current Deployment's resource request(s) is lower than the current Pods' request mutated by Tortoise,
+	// this CLI patches the deployment so that changing tortoise to Off won't result in lowering the resource request(s), damaging the service.
+	noLoweringResource bool
+
+	// Path to KUBECONFIG
+	kubeconfig string
+)
+
+func init() {
+	rootCmd.AddCommand(stopCmd)
+
+	if home := homedir.HomeDir(); home != "" {
+		stopCmd.Flags().StringVar(&kubeconfig, "kubeconfig", filepath.Join(home, ".kube", "config"), "(optional) absolute path to the kubeconfig file")
+	} else {
+		stopCmd.Flags().StringVar(&kubeconfig, "kubeconfig", "", "absolute path to the kubeconfig file")
+	}
+
+	stopCmd.Flags().StringVarP(&stopNamespace, "namespace", "n", "", "namespace to stop tortoise(s) in")
+	stopCmd.Flags().BoolVarP(&stopAll, "all", "A", false, "stop all tortoises in the specified namespace, or in all namespaces if no namespace is specified.")
+	stopCmd.Flags().BoolVar(&noLoweringResource, "no-lowering-resource", false, `Stop tortoise without lowering resource requests. 
+	If this flag is specified and the current Deployment's resource request(s) is lower than the current Pods' request mutated by Tortoise,
+	this CLI patches the deployment so that changing tortoise to Off won't result in lowering the resource request(s), damaging the service.`)
+}
diff --git a/cmd/tortoisectl/main.go b/cmd/tortoisectl/main.go
new file mode 100644
index 00000000..a03dd8ae
--- /dev/null
+++ b/cmd/tortoisectl/main.go
@@ -0,0 +1,7 @@
+package main
+
+import "github.com/mercari/tortoise/cmd/tortoisectl/commands"
+
+func main() {
+	commands.Execute()
+}
diff --git a/cmd/tortoisectl/test/testdata/success/after/deployment.yaml b/cmd/tortoisectl/test/testdata/success/after/deployment.yaml
new file mode 100644
index 00000000..90b761c3
--- /dev/null
+++ b/cmd/tortoisectl/test/testdata/success/after/deployment.yaml
@@ -0,0 +1,48 @@
+metadata:
+  name: mercari-app
+  namespace: test-0
+spec:
+  progressDeadlineSeconds: 600
+  replicas: 1
+  revisionHistoryLimit: 10
+  selector:
+    matchLabels:
+      app: mercari
+  strategy:
+    rollingUpdate:
+      maxSurge: 25%
+      maxUnavailable: 25%
+    type: RollingUpdate
+  template:
+    metadata:
+      annotations:
+        kubectl.kubernetes.io/restartedAt: "2023-01-01T00:00:00Z"
+      creationTimestamp: null
+      labels:
+        app: mercari
+    spec:
+      containers:
+      - image: awesome-mercari-app-image
+        imagePullPolicy: Always
+        name: app
+        resources:
+          requests:
+            cpu: "10"
+            memory: 10Gi
+        terminationMessagePath: /dev/termination-log
+        terminationMessagePolicy: File
+      - image: awesome-istio-proxy-image
+        imagePullPolicy: Always
+        name: istio-proxy
+        resources:
+          requests:
+            cpu: "4"
+            memory: 4Gi
+        terminationMessagePath: /dev/termination-log
+        terminationMessagePolicy: File
+      dnsPolicy: ClusterFirst
+      restartPolicy: Always
+      schedulerName: default-scheduler
+      securityContext: {}
+      terminationGracePeriodSeconds: 30
+status: {}
diff --git a/cmd/tortoisectl/test/testdata/success/after/tortoise.yaml b/cmd/tortoisectl/test/testdata/success/after/tortoise.yaml
new file mode 100644
index 00000000..ab991fee
--- /dev/null
+++ b/cmd/tortoisectl/test/testdata/success/after/tortoise.yaml
@@ -0,0 +1,143 @@
+metadata:
+  finalizers:
+  - tortoise.autoscaling.mercari.com/finalizer
+  name: mercari
+  namespace: test-0
+spec:
+  targetRefs:
+    scaleTargetRef:
+      apiVersion: apps/v1
+      kind: Deployment
+      name: mercari-app
+  updateMode: Auto
+status:
+  autoscalingPolicy:
+  - containerName: app
+    policy:
+      cpu: Horizontal
+      memory: Vertical
+  - containerName: istio-proxy
+    policy:
+      cpu: Horizontal
+      memory: Vertical
+  conditions:
+    containerRecommendationFromVPA:
+    - containerName: app
+      maxRecommendation:
+        cpu:
+          quantity: "3"
+          updatedAt: "2023-01-01T00:00:00Z"
+        memory:
+          quantity: 3Gi
+          updatedAt: "2023-01-01T00:00:00Z"
+      recommendation:
+        cpu:
+          quantity: "3"
+          updatedAt: "2023-01-01T00:00:00Z"
+        memory:
+          quantity: 3Gi
+          updatedAt: "2023-01-01T00:00:00Z"
+    - containerName: istio-proxy
+      maxRecommendation:
+        cpu:
+          quantity: "3"
+          updatedAt: "2023-01-01T00:00:00Z"
+        memory:
+          quantity: 3Gi
+          updatedAt: "2023-01-01T00:00:00Z"
+      recommendation:
+        cpu:
+          quantity: "3"
+          updatedAt: "2023-01-01T00:00:00Z"
+        memory:
+          quantity: 3Gi
+          updatedAt: "2023-01-01T00:00:00Z"
+    containerResourceRequests:
+    - containerName: app
+      resource:
+        cpu: "6"
+        memory: 3Gi
+    - containerName: istio-proxy
+      resource:
+        cpu: "4"
+        memory: 3Gi
+    tortoiseConditions:
+    - lastTransitionTime: "2023-01-01T00:00:00Z"
+      lastUpdateTime: "2023-01-01T00:00:00Z"
+      message: the current number of replicas is not bigger than the preferred max
+        replica number
+      reason: ScaledUpBasedOnPreferredMaxReplicas
+      status: "False"
+      type: ScaledUpBasedOnPreferredMaxReplicas
+    - lastTransitionTime: "2023-01-01T00:00:00Z"
+      lastUpdateTime: "2023-01-01T00:00:00Z"
+      message: HPA target utilization is updated
+      reason: HPATargetUtilizationUpdated
+      status: "True"
+      type: HPATargetUtilizationUpdated
+    - lastTransitionTime: "2023-01-01T00:00:00Z"
+      lastUpdateTime: "2023-01-01T00:00:00Z"
+      message: The recommendation is provided
+      status: "True"
+      type: VerticalRecommendationUpdated
+    - lastTransitionTime: "2023-01-01T00:00:00Z"
+      lastUpdateTime: "2023-01-01T00:00:00Z"
+      status: "False"
+      type: FailedToReconcile
+  containerResourcePhases:
+  - containerName: app
+    resourcePhases:
+      cpu:
+        lastTransitionTime: null
+        phase: Working
+      memory:
+        lastTransitionTime: "2023-01-01T00:00:00Z"
+        phase: Working
+  - containerName: istio-proxy
+    resourcePhases:
+      cpu:
+        lastTransitionTime: null
+        phase: Working
+      memory:
+        lastTransitionTime: "2023-01-01T00:00:00Z"
+        phase: Working
+  recommendations:
+    horizontal:
+      maxReplicas:
+      - from: 0
+        timezone: Local
+        to: 24
+        updatedAt: "2023-01-01T00:00:00Z"
+        value: 20
+      minReplicas:
+      - from: 0
+        timezone: Local
+        to: 24
+        updatedAt: "2023-01-01T00:00:00Z"
+        value: 5
+      targetUtilizations:
+      - containerName: app
+        targetUtilization:
+          cpu: 50
+      - containerName: istio-proxy
+        targetUtilization:
+          cpu: 75
+    vertical:
+      containerResourceRecommendation:
+      - RecommendedResource:
+          cpu: "6"
+          memory: 3Gi
+        containerName: app
+      - RecommendedResource:
+          cpu: "4"
+          memory: 3Gi
+        containerName: istio-proxy
+  targets:
+    horizontalPodAutoscaler: tortoise-hpa-mercari
+    scaleTargetRef:
+      kind: ""
+      name: ""
+    verticalPodAutoscalers:
+    - name: tortoise-monitor-mercari
+      role: Monitor
+  tortoisePhase: Working
diff --git a/cmd/tortoisectl/test/testdata/success/before/deployment.yaml b/cmd/tortoisectl/test/testdata/success/before/deployment.yaml
new file mode 100644
index 00000000..96d10022
--- /dev/null
+++ b/cmd/tortoisectl/test/testdata/success/before/deployment.yaml
@@ -0,0 +1,30 @@
+metadata:
+  name: mercari-app
+  namespace: default
+spec:
+  selector:
+    matchLabels:
+      app: mercari
+  strategy: {}
+  template:
+    metadata:
+      annotations:
+        kubectl.kubernetes.io/restartedAt: "2023-01-01T00:00:00Z"
+      creationTimestamp: null
+      labels:
+        app: mercari
+    spec:
+      containers:
+      - image: awesome-mercari-app-image
+        name: app
+        resources:
+          requests:
+            cpu: "10"
+            memory: 10Gi
+      - image: awesome-istio-proxy-image
+        name: istio-proxy
+        resources:
+          requests:
+            cpu: "4"
+            memory: 4Gi
+status: {}
diff --git a/cmd/tortoisectl/test/testdata/success/before/tortoise.yaml b/cmd/tortoisectl/test/testdata/success/before/tortoise.yaml
new file mode 100644
index 00000000..794f5d48
--- /dev/null
+++ b/cmd/tortoisectl/test/testdata/success/before/tortoise.yaml
@@ -0,0 +1,143 @@
+metadata:
+  finalizers:
+  - tortoise.autoscaling.mercari.com/finalizer
+  name: mercari
+  namespace: default
+spec:
+  updateMode: "Auto"
+  targetRefs:
+    scaleTargetRef:
+      apiVersion: apps/v1
+      kind: Deployment
+      name: mercari-app
+status:
+  autoscalingPolicy:
+  - containerName: app
+    policy:
+      cpu: Horizontal
+      memory: Vertical
+  - containerName: istio-proxy
+    policy:
+      cpu: Horizontal
+      memory: Vertical
+  conditions:
+    containerRecommendationFromVPA:
+    - containerName: app
+      maxRecommendation:
+        cpu:
+          quantity: "3"
+          updatedAt: "2023-01-01T00:00:00Z"
+        memory:
+          quantity: 3Gi
+          updatedAt: "2023-01-01T00:00:00Z"
+      recommendation:
+        cpu:
+          quantity: "3"
+          updatedAt: "2023-01-01T00:00:00Z"
+        memory:
+          quantity: 3Gi
+          updatedAt: "2023-01-01T00:00:00Z"
+    - containerName: istio-proxy
+      maxRecommendation:
+        cpu:
+          quantity: "3"
+          updatedAt: "2023-01-01T00:00:00Z"
+        memory:
+          quantity: 3Gi
+          updatedAt: "2023-01-01T00:00:00Z"
+      recommendation:
+        cpu:
+          quantity: "3"
+          updatedAt: "2023-01-01T00:00:00Z"
+        memory:
+          quantity: 3Gi
+          updatedAt: "2023-01-01T00:00:00Z"
+    containerResourceRequests:
+    - containerName: app
+      resource:
+        cpu: "6"
+        memory: 3Gi
+    - containerName: istio-proxy
+      resource:
+        cpu: "4"
+        memory: 3Gi
+    tortoiseConditions:
+    - lastTransitionTime: "2023-01-01T00:00:00Z"
+      lastUpdateTime: "2023-01-01T00:00:00Z"
+      message: the current number of replicas is not bigger than the preferred max
+        replica number
+      reason: ScaledUpBasedOnPreferredMaxReplicas
+      status: "False"
+      type: ScaledUpBasedOnPreferredMaxReplicas
+    - lastTransitionTime: "2023-01-01T00:00:00Z"
+      lastUpdateTime: "2023-01-01T00:00:00Z"
+      message: HPA target utilization is updated
+      reason: HPATargetUtilizationUpdated
+      status: "True"
+      type: HPATargetUtilizationUpdated
+    - lastTransitionTime: "2023-01-01T00:00:00Z"
+      lastUpdateTime: "2023-01-01T00:00:00Z"
+      message: The recommendation is provided
+      status: "True"
+      type: VerticalRecommendationUpdated
+    - lastTransitionTime: "2023-01-01T00:00:00Z"
+      lastUpdateTime: "2023-01-01T00:00:00Z"
+      status: "False"
+      type: FailedToReconcile
+  containerResourcePhases:
+  - containerName: app
+    resourcePhases:
+      cpu:
+        lastTransitionTime: null
+        phase: Working
+      memory:
+        lastTransitionTime: "2023-01-01T00:00:00Z"
+        phase: Working
+  - containerName: istio-proxy
+    resourcePhases:
+      cpu:
+        lastTransitionTime: null
+        phase: Working
+      memory:
+        lastTransitionTime: "2023-01-01T00:00:00Z"
+        phase: Working
+  recommendations:
+    horizontal:
+      maxReplicas:
+      - from: 0
+        timezone: Local
+        to: 24
+        updatedAt: "2023-01-01T00:00:00Z"
+        value: 20
+      minReplicas:
+      - from: 0
+        timezone: Local
+        to: 24
+        updatedAt: "2023-01-01T00:00:00Z"
+        value: 5
+      targetUtilizations:
+      - containerName: app
+        targetUtilization:
+          cpu: 50
+      - containerName: istio-proxy
+        targetUtilization:
+          cpu: 75
+    vertical:
+      containerResourceRecommendation:
+      - RecommendedResource:
+          cpu: "6"
+          memory: 3Gi
+        containerName: app
+      - RecommendedResource:
+          cpu: "4"
+          memory: 3Gi
+        containerName: istio-proxy
+  targets:
+    horizontalPodAutoscaler: tortoise-hpa-mercari
+    scaleTargetRef:
+      kind: ""
+      name: ""
+    verticalPodAutoscalers:
+    - name: tortoise-monitor-mercari
+      role: Monitor
+  tortoisePhase: Working
diff --git a/cmd/tortoisectl/test/tortoisectl_test.go b/cmd/tortoisectl/test/tortoisectl_test.go
new file mode 100644
index 00000000..3eb4e005
--- /dev/null
+++ b/cmd/tortoisectl/test/tortoisectl_test.go
@@ -0,0 +1,290 @@
+package tortoisectl_test
+
+import (
+	"bytes"
+	"context"
+	"errors"
+	"flag"
+	"fmt"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"strings"
+	"testing"
+
+	"github.com/google/go-cmp/cmp"
+	"github.com/mercari/tortoise/api/v1beta3"
+	appv1 "k8s.io/api/apps/v1"
+	v1 "k8s.io/api/core/v1"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/client-go/kubernetes"
+	"k8s.io/client-go/rest"
+	"sigs.k8s.io/controller-runtime/pkg/client"
+	"sigs.k8s.io/controller-runtime/pkg/envtest"
+	"sigs.k8s.io/yaml"
+)
+
+var (
+	update = flag.Bool("update", false, "Whether to update current snapshots instead of testing")
+)
+
+func TestMain(m *testing.M) {
+	flag.Parse()
+
+	os.Exit(m.Run())
+}
+
+func buildTortoiseCtl(t *testing.T) {
+	t.Helper()
+
+	execCommand(t, "go", "build", "-o", "./testdata/bin/tortoisectl", "../main.go")
+}
+
+func prepareCluster(t *testing.T) (*envtest.Environment, *rest.Config) {
+	t.Helper()
+
+	testEnv := &envtest.Environment{
+		CRDDirectoryPaths:     []string{filepath.Join("..", "..", "..", "config", "crd", "bases")},
+		ErrorIfCRDPathMissing: true,
+	}
+
+	// cfg is defined in this file globally.
+	cfg, err := testEnv.Start()
+	if err != nil {
+		t.Fatalf("Failed to start test environment: %v", err)
+	}
+
+	return testEnv, cfg
+}
+
+func destryCluster(t *testing.T, testEnv *envtest.Environment) {
+	t.Helper()
+
+	err := testEnv.Stop()
+	if err != nil {
+		t.Fatalf("Failed to destroy test environment: %v", err)
+	}
+}
+
+func Test_TortoiseCtlStop(t *testing.T) {
+	// Build the latest binary.
+	buildTortoiseCtl(t)
+	testEnv, cfg := prepareCluster(t)
+	defer destryCluster(t, testEnv)
+
+	// create the clientset
+	clientset, err := kubernetes.NewForConfig(cfg)
+	if err != nil {
+		t.Fatalf("Failed to create clientset: %v", err)
+	}
+
+	scheme := runtime.NewScheme()
+	err = v1beta3.AddToScheme(scheme)
+	if err != nil {
+		t.Fatalf("Failed to add scheme: %v", err)
+	}
+	kubeconfig := strings.Split(testEnv.ControlPlane.KubeCtl().Opts[0], "=")[1]
+
+	tortoiseclient, err := client.New(cfg, client.Options{
+		Scheme: scheme,
+	})
+	if err != nil {
+		t.Fatalf("Failed to create client: %v", err)
+	}
+
+	tests := []struct {
+		name    string
+		options []string
+		dir     string
+	}{
+		{
+			name:    "stop tortoise successfully",
+			options: []string{},
+			dir:     "success",
+		},
+	}
+
+	for i, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			namespace := fmt.Sprintf("test-%d", i)
+			// Create a namespace
+			_, err := clientset.CoreV1().Namespaces().Create(context.Background(), &v1.Namespace{
+				ObjectMeta: metav1.ObjectMeta{
+					Name: namespace,
+				},
+			}, metav1.CreateOptions{})
+			if err != nil {
+				t.Fatalf("Failed to create namespace: %v", err)
+			}
+
+			deploymentYaml := fmt.Sprintf("./testdata/%s/before/deployment.yaml", tt.dir)
+			y, err := os.ReadFile(deploymentYaml)
+			if err != nil {
+				t.Fatalf("Failed to read deployment yaml: %v", err)
+			}
+			deploy := &appv1.Deployment{}
+			err = yaml.Unmarshal(y, deploy)
+			if err != nil {
+				t.Fatalf("Failed to unmarshal deployment yaml: %v", err)
+			}
+
+			// Create a deployment
+			deploy.Namespace = namespace
+			_, err = clientset.AppsV1().Deployments(namespace).Create(context.Background(), deploy, metav1.CreateOptions{})
+			if err != nil {
+				t.Fatalf("Failed to create deployment: %v", err)
+			}
+
+			tortoiseYaml := fmt.Sprintf("./testdata/%s/before/tortoise.yaml", tt.dir)
+			y, err = os.ReadFile(tortoiseYaml)
+			if err != nil {
+				t.Fatalf("Failed to read tortoise yaml: %v", err)
+			}
+			tortoise := &v1beta3.Tortoise{}
+			err = yaml.Unmarshal(y, tortoise)
+			if err != nil {
+				t.Fatalf("Failed to unmarshal tortoise yaml: %v", err)
+			}
+
+			// Create a tortoise
+			tortoise.Namespace = namespace
+			status := tortoise.DeepCopy().Status
+			err = tortoiseclient.Create(context.Background(), tortoise)
+			if err != nil {
+				t.Fatalf("Failed to create tortoise: %v", err)
+			}
+
+			v := &v1beta3.Tortoise{}
+			err = tortoiseclient.Get(context.Background(), client.ObjectKey{Namespace: tortoise.Namespace, Name: tortoise.Name}, v)
+			if err != nil {
+				t.Fatalf("Failed to get tortoise: %v", err)
+			}
+			v.Status = status
+			err = tortoiseclient.Status().Update(context.Background(), v)
+			if err != nil {
+				t.Fatalf("Failed to update tortoise status: %v", err)
+			}
+
+			out, _ := execCommand(t, "./testdata/bin/tortoisectl", "stop", "--kubeconfig", kubeconfig, "--namespace", namespace)
+			t.Log(out)
+
+			deploy, err = clientset.AppsV1().Deployments(namespace).Get(context.Background(), deploy.Name, metav1.GetOptions{})
+			if err != nil {
+				t.Fatalf("Failed to get deployment: %v", err)
+			}
+
+			err = tortoiseclient.Get(context.Background(), client.ObjectKeyFromObject(tortoise), tortoise)
+			if err != nil {
+				t.Fatalf("Failed to get tortoise: %v", err)
+			}
+
+			wantDeployment := fmt.Sprintf("./testdata/%s/after/deployment.yaml", tt.dir)
+			wantTortoiseYaml := fmt.Sprintf("./testdata/%s/after/tortoise.yaml", tt.dir)
+			if *update {
+				err = writeToFile(wantDeployment, deploy)
+				if err != nil {
+					t.Fatalf("Failed to write deployment yaml: %v", err)
+				}
+
+				err = writeToFile(wantTortoiseYaml, tortoise)
+				if err != nil {
+					t.Fatalf("Failed to write tortoise yaml: %v", err)
+				}
+
+				return
+			}
+
+			y, err = os.ReadFile(wantDeployment)
+			if err != nil {
+				t.Fatalf("Failed to read deployment yaml: %v", err)
+			}
+			wantDeploy := &appv1.Deployment{}
+			err = yaml.Unmarshal(y, wantDeploy)
+			if err != nil {
+				t.Fatalf("Failed to decode deployment yaml: %v", err)
+			}
+
+			diff := cmp.Diff(wantDeploy, deploy)
+			if diff != "" {
+				t.Fatalf("Deployment mismatch (-want +got):\n%s", diff)
+			}
+
+			y, err = os.ReadFile(wantTortoiseYaml)
+			if err != nil {
+				t.Fatalf("Failed to read tortoise yaml: %v", err)
+			}
+			wantTortoise := &v1beta3.Tortoise{}
+			err = yaml.Unmarshal(y, wantTortoise)
+			if err != nil {
+				t.Fatalf("Failed to decode tortoise yaml: %v", err)
+			}
+
+			diff = cmp.Diff(wantTortoise, tortoise)
+			if diff != "" {
+				t.Fatalf("Tortoise mismatch (-want +got):\n%s", diff)
+			}
+		})
+	}
+}
+
+func writeToFile(path string, r any) error {
+	y, err := yaml.Marshal(r)
+	if err != nil {
+		return err
+	}
+	y, err = removeUnnecessaryFields(y)
+	if err != nil {
+		return err
+	}
+	err = os.WriteFile(path, y, 0644)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func removeUnnecessaryFields(rawdata []byte) ([]byte, error) {
+	data := make(map[string]interface{})
+	err := yaml.Unmarshal(rawdata, &data)
+	if err != nil {
+		return nil, err
+	}
+	meta, ok := data["metadata"]
+	if !ok {
+		return nil, errors.New("no metadata")
+	}
+	typed, ok := meta.(map[string]any)
+	if !ok {
+		return nil, fmt.Errorf("metadata is unexpected type: %T", meta)
+	}
+
+	delete(typed, "creationTimestamp")
+	delete(typed, "managedFields")
+	delete(typed, "resourceVersion")
+	delete(typed, "uid")
+	delete(typed, "generation")
+
+	return yaml.Marshal(data)
+}
+
+func execCommand(t *testing.T, s ...string) (string, string) {
+	t.Helper()
+	cmd := exec.Command(s[0], s[1:]...)
+	fmt.Println(cmd.String())
+
+	var stdout bytes.Buffer
+	var stderr bytes.Buffer
+	cmd.Stdout = &stdout
+	cmd.Stderr = &stderr
+	t.Logf("Running command: %s\n", cmd.String())
+	err := cmd.Run()
+	if err != nil {
+		t.Errorf("Stdout: %s\n", stdout.String())
+		t.Errorf("Stderr: %s\n", stderr.String())
+		t.Fatalf("cmd.Run() failed: %s\n", err.Error())
+	}
+
+	return stdout.String(), stderr.String()
+}
diff --git a/go.mod b/go.mod
index be38279f..b34fb85c 100644
--- a/go.mod
+++ b/go.mod
@@ -23,11 +23,17 @@ require (
 	sigs.k8s.io/yaml v1.3.0
 )
 
+require (
+	github.com/kyokomi/emoji/v2 v2.2.12
+	github.com/spf13/cobra v1.7.0
+	sigs.k8s.io/e2e-framework v0.3.0
+)
+
 require (
 	github.com/beorn7/perks v1.0.1 // indirect
 	github.com/cespare/xxhash/v2 v2.2.0 // indirect
 	github.com/davecgh/go-spew v1.1.1 // indirect
-	github.com/emicklei/go-restful/v3 v3.10.1 // indirect
+	github.com/emicklei/go-restful/v3 v3.10.2 // indirect
 	github.com/evanphx/json-patch v4.12.0+incompatible // indirect
 	github.com/evanphx/json-patch/v5 v5.6.0 // indirect
 	github.com/fsnotify/fsnotify v1.6.0 // indirect
@@ -43,11 +49,13 @@ require (
 	github.com/google/gofuzz v1.2.0 // indirect
 	github.com/google/pprof v0.0.0-20210720184732-4bb14d4b1be1 // indirect
 	github.com/google/uuid v1.3.0 // indirect
-	github.com/imdario/mergo v0.3.6 // indirect
+	github.com/imdario/mergo v0.3.15 // indirect
+	github.com/inconshreveable/mousetrap v1.1.0 // indirect
 	github.com/josharian/intern v1.0.0 // indirect
 	github.com/json-iterator/go v1.1.12 // indirect
 	github.com/mailru/easyjson v0.7.7 // indirect
 	github.com/matttproud/golang_protobuf_extensions v1.0.4 // indirect
+	github.com/moby/spdystream v0.2.0 // indirect
 	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
 	github.com/modern-go/reflect2 v1.0.2 // indirect
 	github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822 // indirect
@@ -57,18 +65,19 @@ require (
 	github.com/prometheus/procfs v0.11.1 // indirect
 	github.com/spf13/pflag v1.0.5 // indirect
 	github.com/stretchr/testify v1.8.3 // indirect
+	github.com/vladimirvivien/gexe v0.2.0 // indirect
 	go.uber.org/atomic v1.10.0 // indirect
 	go.uber.org/multierr v1.11.0 // indirect
-	golang.org/x/net v0.17.0 // indirect
+	golang.org/x/net v0.20.0 // indirect
 	golang.org/x/oauth2 v0.8.0 // indirect
-	golang.org/x/sys v0.13.0 // indirect
-	golang.org/x/term v0.13.0 // indirect
-	golang.org/x/text v0.13.0 // indirect
+	golang.org/x/sys v0.16.0 // indirect
+	golang.org/x/term v0.16.0 // indirect
+	golang.org/x/text v0.14.0 // indirect
 	golang.org/x/time v0.4.0 // indirect
 	golang.org/x/tools v0.9.1 // indirect
 	gomodules.xyz/jsonpatch/v2 v2.3.0 // indirect
 	google.golang.org/appengine v1.6.7 // indirect
-	google.golang.org/protobuf v1.31.0 // indirect
+	google.golang.org/protobuf v1.33.0 // indirect
 	gopkg.in/inf.v0 v0.9.1 // indirect
 	gopkg.in/yaml.v2 v2.4.0 // indirect
 	k8s.io/apiextensions-apiserver v0.27.2 // indirect
diff --git a/go.sum b/go.sum
index 36149e0f..8aa5f79e 100644
--- a/go.sum
+++ b/go.sum
@@ -1,3 +1,5 @@
+github.com/armon/go-socks5 v0.0.0-20160902184237-e75332964ef5 h1:0CwZNZbxp69SHPdPJAN/hZIm0C4OItdklCFmMRWYpio=
+github.com/armon/go-socks5 v0.0.0-20160902184237-e75332964ef5/go.mod h1:wHh0iHkYZB8zMSxRWpUBQtwG5a7fFgvEO+odwuTv2gs=
 github.com/benbjohnson/clock v1.1.0 h1:Q92kusRqC1XV2MjkWETPvjJVqKetz1OzxZB7mHJLju8=
 github.com/benbjohnson/clock v1.1.0/go.mod h1:J11/hYXuz8f4ySSvYwY0FKfm+ezbsZBKZxNJlLklBHA=
 github.com/beorn7/perks v1.0.1 h1:VlbKKnNfV8bJzeqoa4cOKqO6bYr3WgKZxO8Z16+hsOM=
@@ -7,12 +9,13 @@ github.com/cespare/xxhash/v2 v2.2.0/go.mod h1:VGX0DQ3Q6kWi7AoAeZDth3/j3BFtOZR5XL
 github.com/chzyer/logex v1.1.10/go.mod h1:+Ywpsq7O8HXn0nuIou7OrIPyXbp3wmkHB+jjWRnGsAI=
 github.com/chzyer/readline v0.0.0-20180603132655-2972be24d48e/go.mod h1:nSuG5e5PlCu98SY8svDHJxuZscDgtXS6KTTbou5AhLI=
 github.com/chzyer/test v0.0.0-20180213035817-a1ea475d72b1/go.mod h1:Q3SI9o4m/ZMnBNeIyt5eFwwo7qiLfzFZmjNmxjkiQlU=
+github.com/cpuguy83/go-md2man/v2 v2.0.2/go.mod h1:tgQtvFlXSQOSOSIRvRPT7W67SCa46tRHOmNcaadrF8o=
 github.com/creack/pty v1.1.9/go.mod h1:oKZEueFk5CKHvIhNR5MUki03XCEU+Q6VDXinZuGJ33E=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
-github.com/emicklei/go-restful/v3 v3.10.1 h1:rc42Y5YTp7Am7CS630D7JmhRjq4UlEUuEKfrDac4bSQ=
-github.com/emicklei/go-restful/v3 v3.10.1/go.mod h1:6n3XBCmQQb25CM2LCACGz8ukIrRry+4bhvbpWn3mrbc=
+github.com/emicklei/go-restful/v3 v3.10.2 h1:hIovbnmBTLjHXkqEBUz3HGpXZdM7ZrE9fJIZIqlJLqE=
+github.com/emicklei/go-restful/v3 v3.10.2/go.mod h1:6n3XBCmQQb25CM2LCACGz8ukIrRry+4bhvbpWn3mrbc=
 github.com/evanphx/json-patch v4.12.0+incompatible h1:4onqiflcdA9EOZ4RxV643DvftH5pOlLGNtQ5lPWQu84=
 github.com/evanphx/json-patch v4.12.0+incompatible/go.mod h1:50XU6AFN0ol/bzJsmQLiYLvXMP4fmwYFNcr97nuDLSk=
 github.com/evanphx/json-patch/v5 v5.6.0 h1:b91NhWfaz02IuVxO9faSllyAtNXHMPkC5J8sJCLunww=
@@ -53,9 +56,12 @@ github.com/google/pprof v0.0.0-20210720184732-4bb14d4b1be1 h1:K6RDEckDVWvDI9JAJY
 github.com/google/pprof v0.0.0-20210720184732-4bb14d4b1be1/go.mod h1:kpwsk12EmLew5upagYY7GY0pfYCcupk39gWOCRROcvE=
 github.com/google/uuid v1.3.0 h1:t6JiXgmwXMjEs8VusXIJk2BXHsn+wx8BZdTaoZ5fu7I=
 github.com/google/uuid v1.3.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
+github.com/gorilla/websocket v1.4.2/go.mod h1:YR8l580nyteQvAITg2hZ9XVh4b55+EU/adAjf1fMHhE=
 github.com/ianlancetaylor/demangle v0.0.0-20200824232613-28f6c0f3b639/go.mod h1:aSSvb/t6k1mPoxDqO4vJh6VOCGPwU4O0C2/Eqndh1Sc=
-github.com/imdario/mergo v0.3.6 h1:xTNEAn+kxVO7dTZGu0CegyqKZmoWFI0rF8UxjlB2d28=
-github.com/imdario/mergo v0.3.6/go.mod h1:2EnlNZ0deacrJVfApfmtdGgDfMuh/nq6Ok1EcJh5FfA=
+github.com/imdario/mergo v0.3.15 h1:M8XP7IuFNsqUx6VPK2P9OSmsYsI/YFaGil0uD21V3dM=
+github.com/imdario/mergo v0.3.15/go.mod h1:WBLT9ZmE3lPoWsEzCh9LPo3TiwVN+ZKEjmz+hD27ysY=
+github.com/inconshreveable/mousetrap v1.1.0 h1:wN+x4NVGpMsO7ErUn/mUI3vEoE6Jt13X2s0bqwp9tc8=
+github.com/inconshreveable/mousetrap v1.1.0/go.mod h1:vpF70FUmC8bwa3OWnCshd2FqLfsEA9PFc4w1p2J65bw=
 github.com/jessevdk/go-flags v1.4.0/go.mod h1:4FA24M0QyGHXBuZZK/XkWh8h0e1EYbRYJSGM75WSRxI=
 github.com/josharian/intern v1.0.0 h1:vlS4z54oSdjm0bgjRigI+G1HpF+tI+9rE5LLzOg8HmY=
 github.com/josharian/intern v1.0.0/go.mod h1:5DoeVV0s6jJacbCEi61lwdGj/aVlrQvzHFFd8Hwg//Y=
@@ -71,10 +77,14 @@ github.com/kr/pty v1.1.1/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=
 github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
 github.com/kr/text v0.2.0 h1:5Nx0Ya0ZqY2ygV366QzturHI13Jq95ApcVaJBhpS+AY=
 github.com/kr/text v0.2.0/go.mod h1:eLer722TekiGuMkidMxC/pM04lWEeraHUUmBw8l2grE=
+github.com/kyokomi/emoji/v2 v2.2.12 h1:sSVA5nH9ebR3Zji1o31wu3yOwD1zKXQA2z0zUyeit60=
+github.com/kyokomi/emoji/v2 v2.2.12/go.mod h1:JUcn42DTdsXJo1SWanHh4HKDEyPaR5CqkmoirZZP9qE=
 github.com/mailru/easyjson v0.7.7 h1:UGYAvKxe3sBsEDzO8ZeWOSlIQfWFlxbzLZe7hwFURr0=
 github.com/mailru/easyjson v0.7.7/go.mod h1:xzfreul335JAWq5oZzymOObrkdz5UnU4kGfJJLY9Nlc=
 github.com/matttproud/golang_protobuf_extensions v1.0.4 h1:mmDVorXM7PCGKw94cs5zkfA9PSy5pEvNWRP0ET0TIVo=
 github.com/matttproud/golang_protobuf_extensions v1.0.4/go.mod h1:BSXmuO+STAnVfrANrmjBb36TMTDstsz7MSK+HVaYKv4=
+github.com/moby/spdystream v0.2.0 h1:cjW1zVyyoiM0T7b6UoySUFqzXMoqRckQtXwGPiBhOM8=
+github.com/moby/spdystream v0.2.0/go.mod h1:f7i0iNDQJ059oMTcWxx8MA/zKFIuD/lY+0GqbN2Wy8c=
 github.com/modern-go/concurrent v0.0.0-20180228061459-e0a39a4cb421/go.mod h1:6dJC0mAP4ikYIbvyc7fijjWJddQyLn8Ig3JB5CqoB9Q=
 github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd h1:TRLaZ9cD/w8PVh93nsPXa1VrQ6jlwL5oN8l14QlcNfg=
 github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd/go.mod h1:6dJC0mAP4ikYIbvyc7fijjWJddQyLn8Ig3JB5CqoB9Q=
@@ -101,6 +111,9 @@ github.com/prometheus/procfs v0.11.1 h1:xRC8Iq1yyca5ypa9n1EZnWZkt7dwcoRPQwX/5gwa
 github.com/prometheus/procfs v0.11.1/go.mod h1:eesXgaPo1q7lBpVMoMy0ZOFTth9hBn4W/y0/p/ScXhY=
 github.com/rogpeppe/go-internal v1.10.0 h1:TMyTOH3F/DB16zRVcYyreMH6GnZZrwQVAoYjRBZyWFQ=
 github.com/rogpeppe/go-internal v1.10.0/go.mod h1:UQnix2H7Ngw/k4C5ijL5+65zddjncjaFoBhdsK/akog=
+github.com/russross/blackfriday/v2 v2.1.0/go.mod h1:+Rmxgy9KzJVeS9/2gXHxylqXiyQDYRxCVz55jmeOWTM=
+github.com/spf13/cobra v1.7.0 h1:hyqWnYt1ZQShIddO5kBpj3vu05/++x6tJ6dg8EC572I=
+github.com/spf13/cobra v1.7.0/go.mod h1:uLxZILRyS/50WlhOIKD7W6V5bgeIt+4sICxh6uRMrb0=
 github.com/spf13/pflag v1.0.5 h1:iy+VFUOCP1a+8yFto/drg2CJ5u0yRoB7fZw3DKv/JXA=
 github.com/spf13/pflag v1.0.5/go.mod h1:McXfInJRrz4CZXVZOBLb0bTZqETkiAhM9Iw0y3An2Bg=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
@@ -114,6 +127,8 @@ github.com/stretchr/testify v1.8.0/go.mod h1:yNjHg4UonilssWZ8iaSj1OCr/vHnekPRkoO
 github.com/stretchr/testify v1.8.1/go.mod h1:w2LPCIKwWwSfY2zedu0+kehJoqGctiVI29o6fzry7u4=
 github.com/stretchr/testify v1.8.3 h1:RP3t2pwF7cMEbC1dqtB6poj3niw/9gnV4Cjg5oW5gtY=
 github.com/stretchr/testify v1.8.3/go.mod h1:sz/lmYIOXD/1dqDmKjjqLyZ2RngseejIcXlSw2iwfAo=
+github.com/vladimirvivien/gexe v0.2.0 h1:nbdAQ6vbZ+ZNsolCgSVb9Fno60kzSuvtzVh6Ytqi/xY=
+github.com/vladimirvivien/gexe v0.2.0/go.mod h1:LHQL00w/7gDUKIak24n801ABp8C+ni6eBht9vGVst8w=
 github.com/yuin/goldmark v1.1.27/go.mod h1:3hX8gzYuyVAZsxl0MRgGTJEmQBFcNTphYh9decYSb74=
 github.com/yuin/goldmark v1.2.1/go.mod h1:3hX8gzYuyVAZsxl0MRgGTJEmQBFcNTphYh9decYSb74=
 github.com/yuin/goldmark v1.3.5/go.mod h1:mwnBkeHKe2W/ZEtQ+71ViKU8L12m81fl3OWwC1Zlc8k=
@@ -144,8 +159,8 @@ golang.org/x/net v0.0.0-20190620200207-3b0461eec859/go.mod h1:z5CRVTTTmAJ677TzLL
 golang.org/x/net v0.0.0-20200226121028-0de0cce0169b/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
 golang.org/x/net v0.0.0-20201021035429-f5854403a974/go.mod h1:sp8m0HH+o8qH0wwXwYZr8TS3Oi6o0r6Gce1SSxlDquU=
 golang.org/x/net v0.0.0-20210405180319-a5a99cb37ef4/go.mod h1:p54w0d4576C0XHj96bSt6lcn1PtDYWL6XObtHCRCNQM=
-golang.org/x/net v0.17.0 h1:pVaXccu2ozPjCXewfr1S7xza/zcXTity9cCdXQYSjIM=
-golang.org/x/net v0.17.0/go.mod h1:NxSsAGuq816PNPmqtQdLE42eU2Fs7NoRIZrHJAlaCOE=
+golang.org/x/net v0.20.0 h1:aCL9BSgETF1k+blQaYUBx9hJ9LOGP3gAVemcZlf1Kpo=
+golang.org/x/net v0.20.0/go.mod h1:z8BVo6PvndSri0LbOE3hAn0apkU+1YvI6E70E9jsnvY=
 golang.org/x/oauth2 v0.8.0 h1:6dkIjl3j3LtZ/O3sTgZTMsLKSftL/B8Zgq4huOIIUu8=
 golang.org/x/oauth2 v0.8.0/go.mod h1:yr7u4HXZRm1R1kBWqr/xKNqewf0plRYoB7sla+BCIXE=
 golang.org/x/sync v0.0.0-20181221193216-37e7f081c4d4/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
@@ -161,16 +176,16 @@ golang.org/x/sys v0.0.0-20201119102817-f84b799fce68/go.mod h1:h1NjWce9XRLGQEsW7w
 golang.org/x/sys v0.0.0-20210330210617-4fbd30eecc44/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20210510120138-977fb7262007/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.0.0-20220908164124-27713097b956/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/sys v0.13.0 h1:Af8nKPmuFypiUBjVoU9V20FiaFXOcuZI21p0ycVYYGE=
-golang.org/x/sys v0.13.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.16.0 h1:xWw16ngr6ZMtmxDyKyIgsE93KNKz5HKmMa3b8ALHidU=
+golang.org/x/sys v0.16.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
 golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
-golang.org/x/term v0.13.0 h1:bb+I9cTfFazGW51MZqBVmZy7+JEJMouUHTUSKVQLBek=
-golang.org/x/term v0.13.0/go.mod h1:LTmsnFJwVN6bCy1rVCoS+qHT1HhALEFxKncY3WNNh4U=
+golang.org/x/term v0.16.0 h1:m+B6fahuftsE9qjo0VWp2FW0mB3MTJvR0BaMQrq0pmE=
+golang.org/x/term v0.16.0/go.mod h1:yn7UURbUtPyrVJPGPq404EukNFxcm/foM+bV/bfcDsY=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.2/go.mod h1:bEr9sfX3Q8Zfm5fL9x+3itogRgK3+ptLWKqgva+5dAk=
 golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
-golang.org/x/text v0.13.0 h1:ablQoSUd0tRdKxZewP80B+BaqeKJuVhuRxj/dkrun3k=
-golang.org/x/text v0.13.0/go.mod h1:TvPlkZtksWOMsz7fbANvkp4WM8x/WCo/om8BMLbz+aE=
+golang.org/x/text v0.14.0 h1:ScX5w1eTa3QqT8oi6+ziP7dTV1S2+ALU0bI+0zXKWiQ=
+golang.org/x/text v0.14.0/go.mod h1:18ZOQIKpY8NJVqYksKHtTdi31H5itFRjB5/qKTNYzSU=
 golang.org/x/time v0.4.0 h1:Z81tqI5ddIoXDPvVQ7/7CC9TnLM7ubaFG2qXYd5BbYY=
 golang.org/x/time v0.4.0/go.mod h1:3BpzKBy/shNhVucY/MWOyx10tF3SFh9QdLuxbVysPQM=
 golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
@@ -191,8 +206,8 @@ google.golang.org/appengine v1.6.7 h1:FZR1q0exgwxzPzp/aF+VccGrSfxfPpkBqjIIEq3ru6
 google.golang.org/appengine v1.6.7/go.mod h1:8WjMMxjGQR8xUklV/ARdw2HLXBOI7O7uCIDZVag1xfc=
 google.golang.org/protobuf v1.26.0-rc.1/go.mod h1:jlhhOSvTdKEhbULTjvd4ARK9grFBp09yW+WbY/TyQbw=
 google.golang.org/protobuf v1.26.0/go.mod h1:9q0QmTI4eRPtz6boOQmLYwt+qCgq0jsYwAQnmE0givc=
-google.golang.org/protobuf v1.31.0 h1:g0LDEJHgrBl9N9r17Ru3sqWhkIx2NB67okBHPwC7hs8=
-google.golang.org/protobuf v1.31.0/go.mod h1:HV8QOd/L58Z+nl8r43ehVNZIU/HEI6OcFqwMG9pJV4I=
+google.golang.org/protobuf v1.33.0 h1:uNO2rsAINq/JlFpSdYEKIZ0uKD/R9cpdv0T+yoGwGmI=
+google.golang.org/protobuf v1.33.0/go.mod h1:c6P6GXX6sHbq/GpV6MGZEdwhWPcYBgnhAHhKbcUYpos=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c h1:Hei/4ADfdWqJk1ZMxUNpqntNwaWcugrBjAiHlqqRiVk=
@@ -225,6 +240,8 @@ k8s.io/utils v0.0.0-20240102154912-e7106e64919e h1:eQ/4ljkx21sObifjzXwlPKpdGLrCf
 k8s.io/utils v0.0.0-20240102154912-e7106e64919e/go.mod h1:OLgZIPagt7ERELqWJFomSt595RzquPNLL48iOWgYOg0=
 sigs.k8s.io/controller-runtime v0.15.1 h1:9UvgKD4ZJGcj24vefUFgZFP3xej/3igL9BsOUTb/+4c=
 sigs.k8s.io/controller-runtime v0.15.1/go.mod h1:7ngYvp1MLT+9GeZ+6lH3LOlcHkp/+tzA/fmHa4iq9kk=
+sigs.k8s.io/e2e-framework v0.3.0 h1:eqQALBtPCth8+ulTs6lcPK7ytV5rZSSHJzQHZph4O7U=
+sigs.k8s.io/e2e-framework v0.3.0/go.mod h1:C+ef37/D90Dc7Xq1jQnNbJYscrUGpxrWog9bx2KIa+c=
 sigs.k8s.io/json v0.0.0-20221116044647-bc3834ca7abd h1:EDPBXCAspyGV4jQlpZSudPeMmr1bNJefnuqLsRAsHZo=
 sigs.k8s.io/json v0.0.0-20221116044647-bc3834ca7abd/go.mod h1:B8JuhiUyNFVKdsE8h686QcCxMaH6HrOAZj4vswFpcB0=
 sigs.k8s.io/structured-merge-diff/v4 v4.2.3 h1:PRbqxJClWWYMNV1dhaG4NsibJbArud9kFxnAMREiWFE=
diff --git a/pkg/pod/pod.go b/pkg/pod/pod.go
index 07c409ec..43a9fff7 100644
--- a/pkg/pod/pod.go
+++ b/pkg/pod/pod.go
@@ -42,7 +42,13 @@ func New(
 	}, nil
 }
 
-func (s *Service) ModifyPodResource(pod *v1.Pod, t *v1beta3.Tortoise) {
+type ModifyPodSpecResourceOption string
+
+var (
+	NoScaleDown ModifyPodSpecResourceOption = "NoScaleDown"
+)
+
+func (s *Service) ModifyPodSpecResource(podSpec *v1.PodSpec, t *v1beta3.Tortoise, opts ...ModifyPodSpecResourceOption) {
 	if t.Spec.UpdateMode == v1beta3.UpdateModeOff ||
 		t.Status.TortoisePhase == "" ||
 		t.Status.TortoisePhase == v1beta3.TortoisePhaseInitializing ||
@@ -56,22 +62,26 @@ func (s *Service) ModifyPodResource(pod *v1.Pod, t *v1beta3.Tortoise) {
 	newRequestsMap := map[containerNameAndResource]resource.Quantity{}
 
 	// Update resource requests based on the tortoise.Status.Conditions.ContainerResourceRequests
-	for i, container := range pod.Spec.Containers {
+	for i, container := range podSpec.Containers {
 		for k, oldReq := range container.Resources.Requests {
 			newReq, ok := utils.GetRequestFromTortoise(t, container.Name, k)
 			if !ok {
 				// Unchange, just store the old value as a new value
 				newReq = oldReq
 			}
+			if containsOption(opts, NoScaleDown) && newReq.Cmp(oldReq) < 0 {
+				// If NoScaleDown option is specified, don't scale down the resource request.
+				newReq = oldReq
+			}
 			oldRequestsMap[containerNameAndResource{containerName: container.Name, resourceName: k}] = oldReq
 			newRequestsMap[containerNameAndResource{containerName: container.Name, resourceName: k}] = newReq
-			pod.Spec.Containers[i].Resources.Requests[k] = newReq
+			podSpec.Containers[i].Resources.Requests[k] = newReq
 			requestChangeRatio[containerNameAndResource{containerName: container.Name, resourceName: k}] = float64(newReq.MilliValue()) / float64(oldReq.MilliValue())
 		}
 	}
 
 	// Update resource limits
-	for i, container := range pod.Spec.Containers {
+	for i, container := range podSpec.Containers {
 		if container.Resources.Limits == nil {
 			container.Resources.Limits = make(v1.ResourceList)
 		}
@@ -98,12 +108,12 @@ func (s *Service) ModifyPodResource(pod *v1.Pod, t *v1beta3.Tortoise) {
 			if k == v1.ResourceCPU && newLim.Cmp(s.minimumCPULimit) < 0 {
 				newLim = ptr.To(s.minimumCPULimit.DeepCopy())
 			}
-			pod.Spec.Containers[i].Resources.Limits[k] = *newLim
+			podSpec.Containers[i].Resources.Limits[k] = *newLim
 		}
 	}
 
 	// Update GOMEMLIMIT and GOMAXPROCS
-	for i, container := range pod.Spec.Containers {
+	for i, container := range podSpec.Containers {
 		for j, env := range container.Env {
 			if env.Name == "GOMAXPROCS" {
 				// e.g., If CPU is increased twice, GOMAXPROCS should be doubled.
@@ -126,7 +136,7 @@ func (s *Service) ModifyPodResource(pod *v1.Pod, t *v1beta3.Tortoise) {
 				newUncapedNum := float64(oldNum) * changeRatio
 				// GOMAXPROCS should be an integer.
 				newNum := int(math.Ceil(newUncapedNum))
-				pod.Spec.Containers[i].Env[j].Value = strconv.Itoa(newNum)
+				podSpec.Containers[i].Env[j].Value = strconv.Itoa(newNum)
 
 			}
 
@@ -166,7 +176,7 @@ func (s *Service) ModifyPodResource(pod *v1.Pod, t *v1beta3.Tortoise) {
 				}
 				// See GOMEMLIMIT's format: https://pkg.go.dev/runtime#hdr-Environment_Variables
 				newNum := int(float64(oldNum.Value()) * changeRatio)
-				pod.Spec.Containers[i].Env[j].Value = strconv.Itoa(newNum)
+				podSpec.Containers[i].Env[j].Value = strconv.Itoa(newNum)
 			}
 		}
 	}
@@ -216,3 +226,12 @@ type containerNameAndResource struct {
 	containerName string
 	resourceName  v1.ResourceName
 }
+
+func containsOption(opts []ModifyPodSpecResourceOption, opt ModifyPodSpecResourceOption) bool {
+	for _, o := range opts {
+		if o == opt {
+			return true
+		}
+	}
+	return false
+}
diff --git a/pkg/pod/pod_test.go b/pkg/pod/pod_test.go
index 63b0610e..20cab038 100644
--- a/pkg/pod/pod_test.go
+++ b/pkg/pod/pod_test.go
@@ -13,7 +13,7 @@ import (
 	"github.com/mercari/tortoise/pkg/features"
 )
 
-func TestService_ModifyPodResource(t *testing.T) {
+func TestService_ModifyPodSpecResource(t *testing.T) {
 	type fields struct {
 		resourceLimitMultiplier map[string]int64
 		minimumCPULimit         string
@@ -22,6 +22,7 @@ func TestService_ModifyPodResource(t *testing.T) {
 	type args struct {
 		pod      *v1.Pod
 		tortoise *v1beta3.Tortoise
+		opts     []ModifyPodSpecResourceOption
 	}
 	tests := []struct {
 		name   string
@@ -415,6 +416,69 @@ func TestService_ModifyPodResource(t *testing.T) {
 				},
 			},
 		},
+		{
+			name: "Tortoise is Auto; NoScaleDown option",
+			args: args{
+				opts: []ModifyPodSpecResourceOption{NoScaleDown},
+				pod: &v1.Pod{
+					Spec: v1.PodSpec{
+						Containers: []v1.Container{
+							{
+								Name: "container",
+								Resources: v1.ResourceRequirements{
+									Requests: v1.ResourceList{
+										v1.ResourceCPU:    resource.MustParse("100m"),
+										v1.ResourceMemory: resource.MustParse("100Mi"),
+									},
+									Limits: v1.ResourceList{
+										v1.ResourceCPU:    resource.MustParse("300m"),
+										v1.ResourceMemory: resource.MustParse("100Mi"),
+									},
+								},
+							},
+						},
+					},
+				},
+				tortoise: &v1beta3.Tortoise{
+					Spec: v1beta3.TortoiseSpec{
+						UpdateMode: v1beta3.UpdateModeAuto,
+					},
+					Status: v1beta3.TortoiseStatus{
+						TortoisePhase: v1beta3.TortoisePhaseWorking,
+						Conditions: v1beta3.Conditions{
+							ContainerResourceRequests: []v1beta3.ContainerResourceRequests{
+								{
+									ContainerName: "container",
+									Resource: v1.ResourceList{
+										v1.ResourceCPU:    resource.MustParse("200m"), // scale up
+										v1.ResourceMemory: resource.MustParse("1Mi"),  // scale down
+									},
+								},
+							},
+						},
+					},
+				},
+			},
+			want: &v1.Pod{
+				Spec: v1.PodSpec{
+					Containers: []v1.Container{
+						{
+							Name: "container",
+							Resources: v1.ResourceRequirements{
+								Requests: v1.ResourceList{
+									v1.ResourceCPU:    resource.MustParse("200m"),  // scale up
+									v1.ResourceMemory: resource.MustParse("100Mi"), // scale down is ignored
+								},
+								Limits: v1.ResourceList{
+									v1.ResourceCPU:    resource.MustParse("600m"),
+									v1.ResourceMemory: resource.MustParse("100Mi"),
+								},
+							},
+						},
+					},
+				},
+			},
+		},
 		{
 			name: "Tortoise is Auto; hits resourceLimitMultiplier",
 			fields: fields{
@@ -895,8 +959,8 @@ func TestService_ModifyPodResource(t *testing.T) {
 				t.Fatalf("New() error = %v", err)
 			}
 			got := tt.args.pod.DeepCopy()
-			s.ModifyPodResource(got, tt.args.tortoise)
-			if d := cmp.Diff(got, tt.want); d != "" {
+			s.ModifyPodSpecResource(&got.Spec, tt.args.tortoise, tt.args.opts...)
+			if d := cmp.Diff(got.Spec, tt.want.Spec); d != "" {
 				t.Errorf("ModifyPodResource() mismatch (-want +got):\n%s", d)
 			}
 		})
diff --git a/pkg/stoper/stoper.go b/pkg/stoper/stoper.go
new file mode 100644
index 00000000..3eefe1d3
--- /dev/null
+++ b/pkg/stoper/stoper.go
@@ -0,0 +1,170 @@
+package stoper
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"io"
+	"reflect"
+	"time"
+
+	"github.com/kyokomi/emoji/v2"
+	"github.com/mercari/tortoise/api/v1beta3"
+	"github.com/mercari/tortoise/pkg/deployment"
+	"github.com/mercari/tortoise/pkg/pod"
+	v1 "k8s.io/api/apps/v1"
+	"k8s.io/apimachinery/pkg/types"
+	"sigs.k8s.io/controller-runtime/pkg/client"
+)
+
+// Stopr is the struct for stopping tortoise safely.
+type Stopr struct {
+	c client.Client
+
+	deploymentService *deployment.Service
+	podService        *pod.Service
+}
+
+func New(c client.Client, ds *deployment.Service, ps *pod.Service) *Stopr {
+	return &Stopr{
+		c:                 c,
+		deploymentService: ds,
+		podService:        ps,
+	}
+}
+
+type StoprOption string
+
+var (
+	NoLoweringResource StoprOption = "NoLoweringResource"
+)
+
+func (s *Stopr) Stop(ctx context.Context, tortoiseNames []string, namespace string, all bool, writer io.Writer, opts ...StoprOption) error {
+	// It assumes the validation is already done in the CLI layer.
+
+	targets := []types.NamespacedName{}
+	if all {
+		tortoises := &v1beta3.TortoiseList{}
+		opt := &client.ListOptions{}
+		if namespace != "" {
+			// stop all tortoises in the namespace
+			opt.Namespace = namespace
+		}
+
+		if err := s.c.List(ctx, tortoises); err != nil {
+			return fmt.Errorf("failed to list tortoises: %w", err)
+		}
+
+		for _, t := range tortoises.Items {
+			targets = append(targets, types.NamespacedName{Name: t.Name, Namespace: t.Namespace})
+		}
+	} else {
+		for _, name := range tortoiseNames {
+			targets = append(targets, types.NamespacedName{Name: name, Namespace: namespace})
+		}
+	}
+
+	var finalerr error
+	for _, target := range targets {
+		writer.Write([]byte(fmt.Sprintf("%s stopping your tortoise %s...\n", emoji.Sprint(":turtle:"), &target)))
+
+		// 1. Stop Tortoise.
+		tortoise, err := s.stopOne(ctx, target)
+		if err != nil {
+			if errors.Is(err, errTortoiseAlreadyStopped) {
+				writer.Write([]byte(fmt.Sprintf("%s this tortoise %s is already stopped...\n", emoji.Sprint(":sleeping:"), &target)))
+				continue
+			}
+			finalerr = errors.Join(finalerr, err)
+			writer.Write([]byte(fmt.Sprintf("%s failed to stop your tortoise %s.\nError: %v\n", emoji.Sprint(":face_with_spiral_eyes:"), &target, err)))
+			continue
+		}
+		writer.Write([]byte(fmt.Sprintf("%s stopped your tortoise %s\n", emoji.Sprint(":sleeping:"), &target)))
+
+		// 2. Get the target deployment.
+		dp, err := s.deploymentService.GetDeploymentOnTortoise(ctx, tortoise)
+		if err != nil {
+			finalerr = errors.Join(finalerr, err)
+			writer.Write([]byte(fmt.Sprintf("%s failed to get deployment on your tortoise %s.\nError: %v\n", emoji.Sprint(":face_with_spiral_eyes:"), &target, err)))
+			continue
+		}
+
+		// 3. [when NoLoweringResource is true] Patch the deployment to keep the resource requests high.
+		if containsOption(opts, NoLoweringResource) {
+			writer.Write([]byte(fmt.Sprintf("%s patching your deployment to keep the resource requests high...\n", emoji.Sprint(":hammer_and_wrench:"))))
+			updated, err := s.patchDeploymentToKeepResources(ctx, dp, tortoise)
+			if err != nil {
+				finalerr = errors.Join(finalerr, err)
+				writer.Write([]byte(fmt.Sprintf("%s failed to patch your deployment %s.\nError: %v\n", emoji.Sprint(":face_with_spiral_eyes:"), &target, err)))
+				continue
+			}
+			if updated {
+				// If the deployment is updated, we don't need to restart the deployment.
+				continue
+			}
+		}
+
+		// 4. Restart the deployment to get back the original resource requests.
+		writer.Write([]byte(fmt.Sprintf("%s restarting your deployment to get back the original resource...\n", emoji.Sprint(":sleeping:"))))
+		if err := s.deploymentService.RolloutRestart(ctx, dp, tortoise, time.Now()); err != nil {
+			finalerr = errors.Join(finalerr, err)
+			writer.Write([]byte(fmt.Sprintf("%s failed to restart your deployment %s.\nError: %v\n", emoji.Sprint(":face_with_spiral_eyes:"), &target, err)))
+			continue
+		}
+		writer.Write([]byte(fmt.Sprintf("%s restarted your deployment and your Pods should get back the original resource soon.\n", emoji.Sprint(":muscle:"))))
+	}
+
+	return finalerr
+}
+
+func containsOption(opts []StoprOption, opt StoprOption) bool {
+	for _, o := range opts {
+		if o == opt {
+			return true
+		}
+	}
+	return false
+}
+
+// patchDeploymentToKeepResources patches the deployment to keep the resource requests high.
+// The first return value indicates whether the deployment is updated or not.
+func (s *Stopr) patchDeploymentToKeepResources(ctx context.Context, dp *v1.Deployment, tortoise *v1beta3.Tortoise) (bool, error) {
+	originalDP := dp.DeepCopy()
+
+	// Set to Auto because ModifyPodSpecResource doesn't change anything if it's set to Off.
+	tortoise.Spec.UpdateMode = v1beta3.UpdateModeAuto
+	s.podService.ModifyPodSpecResource(&dp.Spec.Template.Spec, tortoise, pod.NoScaleDown)
+	tortoise.Spec.UpdateMode = v1beta3.UpdateModeOff
+	// If not updated, early return
+	if reflect.DeepEqual(originalDP.Spec.Template.Spec.Containers, dp.Spec.Template.Spec.Containers) {
+		return false, nil
+	}
+
+	if err := s.c.Update(ctx, dp); err != nil {
+		return false, fmt.Errorf("failed to update deployment: %w", err)
+	}
+
+	return true, nil
+}
+
+var errTortoiseAlreadyStopped = errors.New("tortoise is already stopped")
+
+// stopOne disables the tortoise.
+func (s *Stopr) stopOne(ctx context.Context, target types.NamespacedName) (*v1beta3.Tortoise, error) {
+	t := &v1beta3.Tortoise{}
+	if err := s.c.Get(ctx, target, t); err != nil {
+		return nil, fmt.Errorf("failed to get tortoise: %w", err)
+	}
+
+	if t.Spec.UpdateMode == v1beta3.UpdateModeOff {
+		return t, errTortoiseAlreadyStopped
+	}
+
+	t.Spec.UpdateMode = v1beta3.UpdateModeOff
+
+	if err := s.c.Update(ctx, t); err != nil {
+		return nil, fmt.Errorf("failed to update tortoise: %w", err)
+	}
+
+	return t, nil
+}