diff --git a/api/core/v1beta1/openstackcontrolplane_webhook.go b/api/core/v1beta1/openstackcontrolplane_webhook.go
index f4a32fce3..d9c76bcb0 100644
--- a/api/core/v1beta1/openstackcontrolplane_webhook.go
+++ b/api/core/v1beta1/openstackcontrolplane_webhook.go
@@ -530,7 +530,11 @@ func (r *OpenStackControlPlane) ValidateCreateServices(basePath *field.Path) (ad
 	}
 
 	if r.Spec.Rabbitmq.Enabled {
-		if r.Spec.Rabbitmq.Templates != nil {
+		if r.Spec.Rabbitmq.Templates == nil || len(*r.Spec.Rabbitmq.Templates) == 0 {
+			err := field.Required(basePath.Child("rabbitmq").Child("templates"),
+				"At least one RabbitMQ instance must be defined when rabbitmq is enabled")
+			errors = append(errors, err)
+		} else {
 			err := common_webhook.ValidateDNS1123Label(
 				basePath.Child("rabbitmq").Child("templates"),
 				maps.Keys(*r.Spec.Rabbitmq.Templates),
@@ -745,19 +749,24 @@ func (r *OpenStackControlPlane) ValidateUpdateServices(old OpenStackControlPlane
 		if old.Rabbitmq.Templates == nil {
 			old.Rabbitmq.Templates = &map[string]rabbitmqv1.RabbitMqSpecCore{}
 		}
-		if r.Spec.Rabbitmq.Templates != nil {
+		if r.Spec.Rabbitmq.Templates == nil || len(*r.Spec.Rabbitmq.Templates) == 0 {
+			err := field.Required(basePath.Child("rabbitmq").Child("templates"),
+				"At least one RabbitMQ instance must be defined when rabbitmq is enabled")
+			errors = append(errors, err)
+		} else {
 			err := common_webhook.ValidateDNS1123Label(
 				basePath.Child("rabbitmq").Child("templates"),
 				maps.Keys(*r.Spec.Rabbitmq.Templates),
 				memcachedv1.CrMaxLengthCorrection) // omit issue with statefulset pod label "controller-revision-hash": "<statefulset_name>-<hash>"
 			errors = append(errors, err...)
-		}
-		oldRabbitmqs := *old.Rabbitmq.Templates
-		for rabbitmqName, rabbitmqSpec := range *r.Spec.Rabbitmq.Templates {
-			if oldRabbitmq, ok := oldRabbitmqs[rabbitmqName]; ok {
-				warn, errs := rabbitmqSpec.ValidateUpdate(oldRabbitmq, basePath.Child("rabbitmq").Child("template").Key(rabbitmqName), r.Namespace)
-				warnings = append(warnings, warn...)
-				errors = append(errors, errs...)
+
+			oldRabbitmqs := *old.Rabbitmq.Templates
+			for rabbitmqName, rabbitmqSpec := range *r.Spec.Rabbitmq.Templates {
+				if oldRabbitmq, ok := oldRabbitmqs[rabbitmqName]; ok {
+					warn, errs := rabbitmqSpec.ValidateUpdate(oldRabbitmq, basePath.Child("rabbitmq").Child("template").Key(rabbitmqName), r.Namespace)
+					warnings = append(warnings, warn...)
+					errors = append(errors, errs...)
+				}
 			}
 		}
 	}
diff --git a/api/core/v1beta1/openstackcontrolplane_webhook_test.go b/api/core/v1beta1/openstackcontrolplane_webhook_test.go
index 877393361..50ef7ec45 100644
--- a/api/core/v1beta1/openstackcontrolplane_webhook_test.go
+++ b/api/core/v1beta1/openstackcontrolplane_webhook_test.go
@@ -942,4 +942,131 @@ var _ = Describe("OpenStackControlPlane Webhook", func() {
 			})
 		})
 	})
+
+	Context("ValidateCreateServices - RabbitMQ instance requirement", func() {
+		var instance *OpenStackControlPlane
+		var basePath *field.Path
+
+		BeforeEach(func() {
+			instance = &OpenStackControlPlane{
+				ObjectMeta: metav1.ObjectMeta{
+					Name:      "test-controlplane",
+					Namespace: "openstack",
+				},
+				Spec: OpenStackControlPlaneSpec{
+					Rabbitmq: RabbitmqSection{
+						Enabled: true,
+					},
+				},
+			}
+			basePath = field.NewPath("spec")
+		})
+
+		It("should fail when RabbitMQ is enabled but no instances are defined (nil templates)", func() {
+			instance.Spec.Rabbitmq.Templates = nil
+
+			warnings, errs := instance.ValidateCreateServices(basePath)
+			Expect(warnings).To(BeEmpty())
+			Expect(errs).To(HaveLen(1))
+			Expect(errs[0].Type).To(Equal(field.ErrorTypeRequired))
+			Expect(errs[0].Field).To(Equal("spec.rabbitmq.templates"))
+			Expect(errs[0].Detail).To(ContainSubstring("At least one RabbitMQ instance must be defined"))
+		})
+
+		It("should fail when RabbitMQ is enabled but no instances are defined (empty templates)", func() {
+			emptyTemplates := map[string]rabbitmqv1.RabbitMqSpecCore{}
+			instance.Spec.Rabbitmq.Templates = &emptyTemplates
+
+			warnings, errs := instance.ValidateCreateServices(basePath)
+			Expect(warnings).To(BeEmpty())
+			Expect(errs).To(HaveLen(1))
+			Expect(errs[0].Type).To(Equal(field.ErrorTypeRequired))
+			Expect(errs[0].Field).To(Equal("spec.rabbitmq.templates"))
+			Expect(errs[0].Detail).To(ContainSubstring("At least one RabbitMQ instance must be defined"))
+		})
+
+		It("should succeed when RabbitMQ is enabled and at least one instance is defined", func() {
+			templates := map[string]rabbitmqv1.RabbitMqSpecCore{
+				"rabbitmq": {},
+			}
+			instance.Spec.Rabbitmq.Templates = &templates
+
+			warnings, errs := instance.ValidateCreateServices(basePath)
+			Expect(warnings).To(BeEmpty())
+			Expect(errs).To(BeEmpty())
+		})
+
+		It("should succeed when RabbitMQ is disabled and no instances are defined", func() {
+			instance.Spec.Rabbitmq.Enabled = false
+			instance.Spec.Rabbitmq.Templates = nil
+
+			warnings, errs := instance.ValidateCreateServices(basePath)
+			Expect(warnings).To(BeEmpty())
+			Expect(errs).To(BeEmpty())
+		})
+	})
+
+	Context("ValidateUpdateServices - RabbitMQ instance requirement", func() {
+		var instance *OpenStackControlPlane
+		var oldSpec OpenStackControlPlaneSpec
+		var basePath *field.Path
+
+		BeforeEach(func() {
+			oldTemplates := map[string]rabbitmqv1.RabbitMqSpecCore{
+				"rabbitmq": {},
+			}
+			oldSpec = OpenStackControlPlaneSpec{
+				Rabbitmq: RabbitmqSection{
+					Enabled:   true,
+					Templates: &oldTemplates,
+				},
+			}
+
+			instance = &OpenStackControlPlane{
+				ObjectMeta: metav1.ObjectMeta{
+					Name:      "test-controlplane",
+					Namespace: "openstack",
+				},
+				Spec: OpenStackControlPlaneSpec{
+					Rabbitmq: RabbitmqSection{
+						Enabled: true,
+					},
+				},
+			}
+			basePath = field.NewPath("spec")
+		})
+
+		It("should fail when trying to remove all RabbitMQ instances while enabled", func() {
+			emptyTemplates := map[string]rabbitmqv1.RabbitMqSpecCore{}
+			instance.Spec.Rabbitmq.Templates = &emptyTemplates
+
+			warnings, errs := instance.ValidateUpdateServices(oldSpec, basePath)
+			Expect(warnings).To(BeEmpty())
+			Expect(errs).To(HaveLen(1))
+			Expect(errs[0].Type).To(Equal(field.ErrorTypeRequired))
+			Expect(errs[0].Field).To(Equal("spec.rabbitmq.templates"))
+			Expect(errs[0].Detail).To(ContainSubstring("At least one RabbitMQ instance must be defined"))
+		})
+
+		It("should succeed when updating with at least one RabbitMQ instance", func() {
+			templates := map[string]rabbitmqv1.RabbitMqSpecCore{
+				"rabbitmq": {},
+			}
+			instance.Spec.Rabbitmq.Templates = &templates
+
+			warnings, errs := instance.ValidateUpdateServices(oldSpec, basePath)
+			Expect(warnings).To(BeEmpty())
+			Expect(errs).To(BeEmpty())
+		})
+
+		It("should succeed when disabling RabbitMQ and removing all instances", func() {
+			instance.Spec.Rabbitmq.Enabled = false
+			emptyTemplates := map[string]rabbitmqv1.RabbitMqSpecCore{}
+			instance.Spec.Rabbitmq.Templates = &emptyTemplates
+
+			warnings, errs := instance.ValidateUpdateServices(oldSpec, basePath)
+			Expect(warnings).To(BeEmpty())
+			Expect(errs).To(BeEmpty())
+		})
+	})
 })