diff --git a/api/v1alpha1/mysqlcluster_types.go b/api/v1alpha1/mysqlcluster_types.go
index 932a7e467..26821755c 100644
--- a/api/v1alpha1/mysqlcluster_types.go
+++ b/api/v1alpha1/mysqlcluster_types.go
@@ -31,7 +31,7 @@ type MysqlClusterSpec struct {
 
 	// Replicas is the number of pods.
 	// +optional
-	// +kubebuilder:validation:Enum=0;2;3;5
+	// +kubebuilder:validation:Enum=0;1;2;3;5
 	// +kubebuilder:default:=3
 	Replicas *int32 `json:"replicas,omitempty"`
 
diff --git a/charts/mysql-operator/crds/mysql.radondb.com_mysqlclusters.yaml b/charts/mysql-operator/crds/mysql.radondb.com_mysqlclusters.yaml
index 88d891c56..2472051bd 100644
--- a/charts/mysql-operator/crds/mysql.radondb.com_mysqlclusters.yaml
+++ b/charts/mysql-operator/crds/mysql.radondb.com_mysqlclusters.yaml
@@ -1259,6 +1259,7 @@ spec:
                 description: Replicas is the number of pods.
                 enum:
                 - 0
+                - 1
                 - 2
                 - 3
                 - 5
diff --git a/config/crd/bases/mysql.radondb.com_mysqlclusters.yaml b/config/crd/bases/mysql.radondb.com_mysqlclusters.yaml
index 88d891c56..2472051bd 100644
--- a/config/crd/bases/mysql.radondb.com_mysqlclusters.yaml
+++ b/config/crd/bases/mysql.radondb.com_mysqlclusters.yaml
@@ -1259,6 +1259,7 @@ spec:
                 description: Replicas is the number of pods.
                 enum:
                 - 0
+                - 1
                 - 2
                 - 3
                 - 5
diff --git a/mysqlcluster/container/xenon.go b/mysqlcluster/container/xenon.go
index 37f520c50..e7bfd8aa9 100644
--- a/mysqlcluster/container/xenon.go
+++ b/mysqlcluster/container/xenon.go
@@ -43,7 +43,11 @@ func (c *xenon) getImage() string {
 
 // getCommand get the container command.
 func (c *xenon) getCommand() []string {
-	return nil
+	if *c.Spec.Replicas == 1 {
+		return []string{"xenon", "-c", "/etc/xenon/xenon.json", "-r", "LEADER"}
+	}
+	// If return nil, statefulset never update command , And I don't know why.
+	return []string{"xenon", "-c", "/etc/xenon/xenon.json"}
 }
 
 // getEnvVars get the container env.
@@ -86,7 +90,7 @@ func (c *xenon) getLifecycle() *corev1.Lifecycle {
 				Command: []string{
 					"/bin/bash",
 					"-c",
-					"/xenonchecker preStop",
+					"timeout 7 /xenonchecker preStop",
 				},
 			},
 		},
@@ -95,7 +99,7 @@ func (c *xenon) getLifecycle() *corev1.Lifecycle {
 				Command: []string{
 					"/bin/bash",
 					"-c",
-					"/xenonchecker postStart",
+					"timeout 7 /xenonchecker postStart",
 				},
 			},
 		},
diff --git a/sidecar/config.go b/sidecar/config.go
index e8b46d96a..a0c41a1f4 100644
--- a/sidecar/config.go
+++ b/sidecar/config.go
@@ -363,8 +363,8 @@ func (cfg *Config) buildXenonConf() []byte {
 			"semi-sync-degrade": true,
 			"purge-binlog-disabled": true,
 			"super-idle": false,
-			"leader-start-command": "/xenonchecker leaderStart",
-			"leader-stop-command": "/xenonchecker leaderStop"
+			"leader-start-command": "timeout 7 /xenonchecker leaderStart",
+			"leader-stop-command": "timeout 7 /xenonchecker leaderStop"
 		}
 	}
 	`, hostName, utils.XenonPort, hostName, utils.XenonPeerPort, cfg.ReplicationPassword, cfg.ReplicationUser,