[BARX-1713] Auto-detect cloud provider for admission controller container registry

pkg/clusteragent/admission/mutate/agent_sidecar/agent_sidecar.go

@@ -85,7 +85,7 @@ func NewWebhook(datadogConfig config.Component) *Webhook {
 
 	nsSelector, objSelector := labelSelectors(datadogConfig, profileOverrides)
 
-	containerRegistry := mutatecommon.ContainerRegistry(datadogConfig, "admission_controller.agent_sidecar.container_registry")
+	containerRegistry := mutatecommon.ContainerRegistry(context.TODO(), datadogConfig, "admission_controller.agent_sidecar.container_registry")
 
 	return &Webhook{
 		name:              webhookName,

pkg/clusteragent/admission/mutate/agent_sidecar/agent_sidecar_test.go

@@ -697,8 +697,8 @@ func TestDefaultSidecarTemplateAgentImage(t *testing.T) {
 		{
 			name:              "no configuration set",
 			setConfig:         func() model.Config { return configmock.New(t) },
-			containerRegistry: commonRegistry,
-			expectedImage:     commonRegistry + "/agent:latest",
+			containerRegistry: "registry.datadoghq.com",
+			expectedImage:     "registry.datadoghq.com/agent:latest",
 		},
 		{
 			name:              "setting custom registry, image and tag",

pkg/clusteragent/admission/mutate/autoinstrumentation/auto_instrumentation_test.go

@@ -1381,7 +1381,7 @@ func TestAutoinstrumentation(t *testing.T) {
 			shouldMutate: true,
 			expected: &expected{
 				initContainerImages: []string{
-					"gcr.io/datadoghq/dd-lib-php-init:v1",
+					"registry.datadoghq.com/dd-lib-php-init:v1",
 					"docker.io/library/apm-inject-package:v27",
 				},
 				containerNames: defaultContainerNames,
@@ -1409,7 +1409,7 @@ func TestAutoinstrumentation(t *testing.T) {
 			shouldMutate: true,
 			expected: &expected{
 				initContainerImages: []string{
-					"gcr.io/datadoghq/apm-inject:0",
+					"registry.datadoghq.com/apm-inject:0",
 					"foo/bar:1",
 				},
 				containerNames: defaultContainerNames,

pkg/clusteragent/admission/mutate/autoinstrumentation/config.go

@@ -8,6 +8,7 @@
 package autoinstrumentation
 
 import (
+	"context"
 	"encoding/json"
 	"errors"
 	"fmt"
@@ -125,7 +126,7 @@ func NewConfig(datadogConfig config.Component) (*Config, error) {
 		return nil, fmt.Errorf("unable to parse init-container's resources from configuration: %w", err)
 	}
 
-	containerRegistry := mutatecommon.ContainerRegistry(datadogConfig, "admission_controller.auto_instrumentation.container_registry")
+	containerRegistry := mutatecommon.ContainerRegistry(context.TODO(), datadogConfig, "admission_controller.auto_instrumentation.container_registry")
 	mutateUnlabelled := datadogConfig.GetBool("admission_controller.mutate_unlabelled")
 
 	return &Config{

pkg/clusteragent/admission/mutate/autoinstrumentation/imageresolver/config_test.go

@@ -33,7 +33,7 @@ func TestNewConfig(t *testing.T) {
 			},
 			expectedState: Config{
 				Site:           "datadoghq.com",
-				DDRegistries:   map[string]struct{}{"gcr.io/datadoghq": {}, "docker.io/datadog": {}, "public.ecr.aws/datadog": {}},
+				DDRegistries:   map[string]struct{}{"gcr.io/datadoghq": {}, "docker.io/datadog": {}, "public.ecr.aws/datadog": {}, "datadoghq.azurecr.io": {}, "registry.datadoghq.com": {}},
 				BucketID:       "2",
 				DigestCacheTTL: 1 * time.Hour,
 				Enabled:        true,
@@ -64,7 +64,7 @@ func TestNewConfig(t *testing.T) {
 			},
 			expectedState: Config{
 				Site:           "datad0g.com",
-				DDRegistries:   map[string]struct{}{"gcr.io/datadoghq": {}, "docker.io/datadog": {}, "public.ecr.aws/datadog": {}},
+				DDRegistries:   map[string]struct{}{"gcr.io/datadoghq": {}, "docker.io/datadog": {}, "public.ecr.aws/datadog": {}, "datadoghq.azurecr.io": {}, "registry.datadoghq.com": {}},
 				BucketID:       "2",
 				DigestCacheTTL: 1 * time.Hour,
 				Enabled:        true,
@@ -80,7 +80,7 @@ func TestNewConfig(t *testing.T) {
 			},
 			expectedState: Config{
 				Site:           "datadoghq.com",
-				DDRegistries:   map[string]struct{}{"gcr.io/datadoghq": {}, "docker.io/datadog": {}, "public.ecr.aws/datadog": {}},
+				DDRegistries:   map[string]struct{}{"gcr.io/datadoghq": {}, "docker.io/datadog": {}, "public.ecr.aws/datadog": {}, "datadoghq.azurecr.io": {}, "registry.datadoghq.com": {}},
 				BucketID:       "0",
 				DigestCacheTTL: 1 * time.Hour,
 				Enabled:        true,
@@ -97,7 +97,7 @@ func TestNewConfig(t *testing.T) {
 			},
 			expectedState: Config{
 				Site:           "datadoghq.com",
-				DDRegistries:   map[string]struct{}{"gcr.io/datadoghq": {}, "docker.io/datadog": {}, "public.ecr.aws/datadog": {}},
+				DDRegistries:   map[string]struct{}{"gcr.io/datadoghq": {}, "docker.io/datadog": {}, "public.ecr.aws/datadog": {}, "datadoghq.azurecr.io": {}, "registry.datadoghq.com": {}},
 				BucketID:       "0",
 				DigestCacheTTL: 1 * time.Hour,
 				Enabled:        false,
@@ -114,7 +114,7 @@ func TestNewConfig(t *testing.T) {
 			},
 			expectedState: Config{
 				Site:           "datadoghq.com",
-				DDRegistries:   map[string]struct{}{"gcr.io/datadoghq": {}, "docker.io/datadog": {}, "public.ecr.aws/datadog": {}},
+				DDRegistries:   map[string]struct{}{"gcr.io/datadoghq": {}, "docker.io/datadog": {}, "public.ecr.aws/datadog": {}, "datadoghq.azurecr.io": {}, "registry.datadoghq.com": {}},
 				BucketID:       "0",
 				DigestCacheTTL: 2 * time.Hour,
 				Enabled:        true,

pkg/clusteragent/admission/mutate/common/common.go

@@ -9,6 +9,7 @@
 package common
 
 import (
+	"context"
 	"encoding/json"
 	"fmt"
 	"slices"
@@ -21,6 +22,7 @@ import (
 
 	"github.com/DataDog/datadog-agent/comp/core/config"
 	"github.com/DataDog/datadog-agent/pkg/clusteragent/admission/metrics"
+	"github.com/DataDog/datadog-agent/pkg/util/kubernetes/cloudprovider"
 	"github.com/DataDog/datadog-agent/pkg/util/log"
 )
 
@@ -195,15 +197,40 @@ func containsVolumeMount(volumeMounts []corev1.VolumeMount, element corev1.Volum
 	return false
 }
 
+// defaultRegistryForProvider returns the preferred container registry for the
+// given cloud provider. This follows the Datadog recommendation of using
+// cloud-provider-specific registries for lower latency and reduced egress.
+func defaultRegistryForProvider(provider string) string {
+	switch provider {
+	case "eks":
+		return "public.ecr.aws/datadog"
+	case "gke":
+		return "gcr.io/datadoghq"
+	case "aks":
+		return "datadoghq.azurecr.io"
+	default:
+		return "registry.datadoghq.com"
+	}
+}
+
 // ContainerRegistry gets the container registry config using the specified
 // config option, and falls back to the default container registry if no
-// webhook-specific container registry is set.
-func ContainerRegistry(datadogConfig config.Component, specificConfigOpt string) string {
-	if datadogConfig.IsSet(specificConfigOpt) {
+// webhook-specific container registry is set. If no global registry is
+// explicitly configured, it auto-selects based on the detected cloud provider,
+// falling back to registry.datadoghq.com.
+func ContainerRegistry(ctx context.Context, datadogConfig config.Component, specificConfigOpt string) string {
+	if datadogConfig.IsConfigured(specificConfigOpt) {
 		return datadogConfig.GetString(specificConfigOpt)
 	}
 
-	return datadogConfig.GetString("admission_controller.container_registry")
+	if datadogConfig.IsConfigured("admission_controller.container_registry") {
+		return datadogConfig.GetString("admission_controller.container_registry")
+	}
+
+	provider := cloudprovider.DCAGetName(ctx)
+	registry := defaultRegistryForProvider(provider)
+	log.Infof("Auto-detected cloud provider %q, using container registry %q", provider, registry)
+	return registry
 }
 
 // MarkVolumeAsSafeToEvictForAutoscaler adds the Kubernetes cluster-autoscaler

pkg/clusteragent/admission/mutate/common/common_test.go

@@ -8,12 +8,15 @@
 package common
 
 import (
+	"context"
 	"reflect"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 	corev1 "k8s.io/api/core/v1"
+
+	configmock "github.com/DataDog/datadog-agent/pkg/config/mock"
 )
 
 func Test_contains(t *testing.T) {
@@ -324,3 +327,66 @@ func TestMarkVolumeAsSafeToEvictForAutoscaler(t *testing.T) {
 	}
 
 }
+
+func Test_defaultRegistryForProvider(t *testing.T) {
+	tests := []struct {
+		provider string
+		expected string
+	}{
+		{"eks", "public.ecr.aws/datadog"},
+		{"gke", "gcr.io/datadoghq"},
+		{"aks", "datadoghq.azurecr.io"},
+		{"", "registry.datadoghq.com"},
+		{"unknown", "registry.datadoghq.com"},
+	}
+
+	for _, tt := range tests {
+		t.Run("provider_"+tt.provider, func(t *testing.T) {
+			assert.Equal(t, tt.expected, defaultRegistryForProvider(tt.provider))
+		})
+	}
+}
+
+func Test_ContainerRegistry(t *testing.T) {
+	tests := []struct {
+		name           string
+		specificKey    string
+		specificValue  string
+		globalValue    string
+		expectedPrefix string
+	}{
+		{
+			name:           "webhook-specific config wins",
+			specificKey:    "admission_controller.auto_instrumentation.container_registry",
+			specificValue:  "my-custom-registry.io/datadog",
+			globalValue:    "global-registry.io/datadog",
+			expectedPrefix: "my-custom-registry.io/datadog",
+		},
+		{
+			name:           "global config used when no specific config",
+			specificKey:    "admission_controller.auto_instrumentation.container_registry",
+			globalValue:    "global-registry.io/datadog",
+			expectedPrefix: "global-registry.io/datadog",
+		},
+		{
+			name:           "auto-detection when no config set",
+			specificKey:    "admission_controller.auto_instrumentation.container_registry",
+			expectedPrefix: "registry.datadoghq.com", // no cloud provider detected in tests → default
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			mockConfig := configmock.New(t)
+			if tt.specificValue != "" {
+				mockConfig.SetWithoutSource(tt.specificKey, tt.specificValue)
+			}
+			if tt.globalValue != "" {
+				mockConfig.SetWithoutSource("admission_controller.container_registry", tt.globalValue)
+			}
+
+			result := ContainerRegistry(context.TODO(), mockConfig, tt.specificKey)
+			assert.Equal(t, tt.expectedPrefix, result)
+		})
+	}
+}

pkg/clusteragent/admission/mutate/cwsinstrumentation/cws_instrumentation.go

@@ -348,7 +348,7 @@ func NewCWSInstrumentation(wmeta workloadmeta.Component, datadogConfig config.Co
 	cwsInjectorImageName := pkgconfigsetup.Datadog().GetString("admission_controller.cws_instrumentation.image_name")
 	cwsInjectorImageTag := pkgconfigsetup.Datadog().GetString("admission_controller.cws_instrumentation.image_tag")
 
-	cwsInjectorContainerRegistry := mutatecommon.ContainerRegistry(datadogConfig, "admission_controller.cws_instrumentation.container_registry")
+	cwsInjectorContainerRegistry := mutatecommon.ContainerRegistry(context.TODO(), datadogConfig, "admission_controller.cws_instrumentation.container_registry")
 
 	if len(cwsInjectorImageName) == 0 {
 		return nil, errors.New("can't initialize CWS Instrumentation without an image_name")

pkg/config/setup/config.go

@@ -951,7 +951,7 @@ func InitConfig(config pkgconfigmodel.Setup) {
 	config.BindEnvAndSetDefault("admission_controller.mutation.enabled", true)
 	config.BindEnvAndSetDefault("admission_controller.mutate_unlabelled", false)
 	config.BindEnvAndSetDefault("admission_controller.port", 8000)
-	config.BindEnvAndSetDefault("admission_controller.container_registry", "gcr.io/datadoghq")
+	config.BindEnvAndSetDefault("admission_controller.container_registry", "registry.datadoghq.com")
 	config.BindEnvAndSetDefault("admission_controller.timeout_seconds", 10) // in seconds (see kubernetes/kubernetes#71508)
 	config.BindEnvAndSetDefault("admission_controller.service_name", "datadog-admission-controller")
 	config.BindEnvAndSetDefault("admission_controller.certificate.validity_bound", 365*24)             // validity bound of the certificate created by the controller (in hours, default 1 year)
@@ -984,6 +984,8 @@ func InitConfig(config pkgconfigmodel.Setup) {
 		"gcr.io/datadoghq",
 		"docker.io/datadog",
 		"public.ecr.aws/datadog",
+		"datadoghq.azurecr.io",
+		"registry.datadoghq.com",
 	})
 	config.BindEnvAndSetDefault("admission_controller.auto_instrumentation.gradual_rollout.enabled", true)
 	config.BindEnvAndSetDefault("admission_controller.auto_instrumentation.gradual_rollout.cache_ttl", "1h")

releasenotes-dca/notes/admission-controller-auto-registry-detection-3e96f82298a87d08.yaml

@@ -0,0 +1,13 @@
+---
+enhancements:
+  - |
+    The admission controller now auto-selects the container registry based on the
+    detected cloud provider (EKS uses ``public.ecr.aws/datadog``, GKE uses
+    ``gcr.io/datadoghq``, AKS uses ``datadoghq.azurecr.io``). The new default for
+    environments where no cloud provider is detected is ``registry.datadoghq.com``
+    (previously ``gcr.io/datadoghq``). Explicit configuration via
+    ``admission_controller.container_registry`` or webhook-specific overrides still
+    takes precedence. To restore the previous behavior, set
+    ``admission_controller.container_registry`` to ``gcr.io/datadoghq`` in your
+    ``datadog.yaml`` or via the ``DD_ADMISSION_CONTROLLER_CONTAINER_REGISTRY``
+    environment variable.

releasenotes/notes/admission-controller-auto-registry-detection-3e96f82298a87d08.yaml

@@ -0,0 +1,11 @@
+---
+enhancements:
+  - |
+    The default container registry for the admission controller has changed from
+    ``gcr.io/datadoghq`` to ``registry.datadoghq.com``. On managed Kubernetes
+    environments, the cluster agent now auto-selects a cloud-provider-specific
+    registry (EKS: ``public.ecr.aws/datadog``, GKE: ``gcr.io/datadoghq``, AKS:
+    ``datadoghq.azurecr.io``) for lower latency and reduced egress. To restore the
+    previous default, set ``admission_controller.container_registry`` to
+    ``gcr.io/datadoghq`` in your ``datadog.yaml`` or via the
+    ``DD_ADMISSION_CONTROLLER_CONTAINER_REGISTRY`` environment variable.