diff --git a/cluster.go b/cluster.go
index e8f84a2f..3e9fb0df 100644
--- a/cluster.go
+++ b/cluster.go
@@ -321,14 +321,11 @@ const DefaultRepairHealthCheckCommandTimeoutSeconds = 30
 const DefaultRepairCommandTimeoutSeconds = 30
 
 type Retire struct {
-	ShutdownCommand       []string `json:"shutdown_command"`
-	CheckCommand          []string `json:"check_command"`
-	CommandTimeoutSeconds *int     `json:"command_timeout_seconds,omitempty"`
-	CheckTimeoutSeconds   *int     `json:"check_timeout_seconds,omitempty"`
+	OptionalCommand               []string `json:"optional_command,omitempty"`
+	OptionalCommandTimeoutSeconds *int     `json:"optional_command_timeout_seconds,omitempty"`
 }
 
-const DefaultRetireCommandTimeoutSeconds = 30
-const DefaultRetireCheckTimeoutSeconds = 300
+const DefaultRetireOptionalCommandTimeoutSeconds = 30
 
 // Options is a set of optional parameters for k8s components.
 type Options struct {
diff --git a/mtest/cke-cluster.yml b/mtest/cke-cluster.yml
index b7058361..ddd10b8e 100644
--- a/mtest/cke-cluster.yml
+++ b/mtest/cke-cluster.yml
@@ -30,10 +30,8 @@ repair:
         watch_seconds: 30
       health_check_command: ["sh", "-c", "test -f /tmp/mtest-repair-$1 && echo true", "health_check"]
 retire:
-  shutdown_command: ["true"]
-  check_command: ["bash", "-c", "echo 'Off'"]
-  command_timeout_seconds: 30
-  check_timeout_seconds: 300
+  optional_command: ["true"]
+  optional_command_timeout_seconds: 30
 options:
   kube-api:
     extra_binds:
diff --git a/op/kube_node_remove.go b/op/kube_node_remove.go
index 7a8798f7..7db7e81e 100644
--- a/op/kube_node_remove.go
+++ b/op/kube_node_remove.go
@@ -7,7 +7,6 @@ import (
 	"time"
 
 	"github.com/cybozu-go/cke"
-	"github.com/cybozu-go/log"
 	"github.com/cybozu-go/well"
 	corev1 "k8s.io/api/core/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
@@ -41,10 +40,8 @@ func (o *kubeNodeRemove) NextCommand() cke.Commander {
 	return nodeRemoveCommand{
 		o.apiserver,
 		o.nodes,
-		o.config.ShutdownCommand,
-		o.config.CheckCommand,
-		o.config.CommandTimeoutSeconds,
-		o.config.CheckTimeoutSeconds,
+		o.config.OptionalCommand,
+		o.config.OptionalCommandTimeoutSeconds,
 	}
 }
 
@@ -55,12 +52,10 @@ func (o *kubeNodeRemove) Targets() []string {
 }
 
 type nodeRemoveCommand struct {
-	apiserver           *cke.Node
-	nodes               []*corev1.Node
-	shutdownCommand     []string
-	checkCommand        []string
-	timeoutSeconds      *int
-	checkTimeoutSeconds *int
+	apiserver                     *cke.Node
+	nodes                         []*corev1.Node
+	optionalCommand               []string
+	optionalCommandTimeoutSeconds *int
 }
 
 func (c nodeRemoveCommand) Run(ctx context.Context, inf cke.Infrastructure, _ string) error {
@@ -92,66 +87,25 @@ func (c nodeRemoveCommand) Run(ctx context.Context, inf cke.Infrastructure, _ st
 				return fmt.Errorf("failed to patch node %s: %v", n.Name, err)
 			}
 		}
-		err := func() error {
-			ctx := ctx
-			timeout := cke.DefaultRetireCommandTimeoutSeconds
-			if c.timeoutSeconds != nil {
-				timeout = *c.timeoutSeconds
-			}
-			if timeout != 0 {
-				var cancel context.CancelFunc
-				ctx, cancel = context.WithTimeout(ctx, time.Second*time.Duration(timeout))
-				defer cancel()
-			}
-			args := append(c.shutdownCommand[1:], n.Name)
-			command := well.CommandContext(ctx, c.shutdownCommand[0], args...)
-			return command.Run()
-		}()
-		if err != nil {
-			return fmt.Errorf("failed to shutdown node %s: %v", n.Name, err)
-		}
-
-		err = func() error {
-			ctx := ctx
-			checkTimeout := cke.DefaultRetireCheckTimeoutSeconds
-			if c.checkTimeoutSeconds != nil {
-				checkTimeout = *c.checkTimeoutSeconds
-			}
-			timeout := time.After(time.Duration(checkTimeout) * time.Second)
-			ticker := time.NewTicker(10 * time.Second)
-			for {
-				select {
-				case <-timeout:
-					return fmt.Errorf("timeout")
-				case <-ticker.C:
-					args := append(c.checkCommand[1:], n.Name)
-					command := well.CommandContext(ctx, c.checkCommand[0], args...)
-					stdout, err := command.Output()
-					if err != nil {
-						log.Warn("failed to check shutdown status of node", map[string]interface{}{
-							log.FnError: err,
-							"node":      n.Name,
-						})
-						continue
-					}
-					if strings.TrimSuffix(string(stdout), "\n") == "Off" {
-						return nil
-					}
+		if len(c.optionalCommand) != 0 {
+			err := func() error {
+				ctx := ctx
+				timeout := cke.DefaultRetireOptionalCommandTimeoutSeconds
+				if c.optionalCommandTimeoutSeconds != nil {
+					timeout = *c.optionalCommandTimeoutSeconds
 				}
+				if timeout != 0 {
+					var cancel context.CancelFunc
+					ctx, cancel = context.WithTimeout(ctx, time.Second*time.Duration(timeout))
+					defer cancel()
+				}
+				args := append(c.optionalCommand[1:], n.Name)
+				command := well.CommandContext(ctx, c.optionalCommand[0], args...)
+				return command.Run()
+			}()
+			if err != nil {
+				return fmt.Errorf("failed to execute optional command in retirement %s: %v", n.Name, err)
 			}
-		}()
-		if err != nil {
-			return fmt.Errorf("failed to check shutdown status of node %s: %v", n.Name, err)
-		}
-		shutdownTaint := corev1.Taint{
-			Key:    "node.kubernetes.io/out-of-service",
-			Value:  "nodeshutdown",
-			Effect: corev1.TaintEffectNoExecute,
-		}
-		n.Spec.Taints = append(n.Spec.Taints, shutdownTaint)
-		_, err = nodesAPI.Update(ctx, n, metav1.UpdateOptions{})
-		if err != nil {
-			return fmt.Errorf("failed to update node %s: %v", n.Name, err)
 		}
 
 		err = nodesAPI.Delete(ctx, n.Name, metav1.DeleteOptions{})