Set dcgm-exporter pod spec DNS policy when setting hostNetwork

Mirroring upstream dcgm-exporter helm chart behavior, set dcgm-exporter
Pod `spec.DNSPolicy` to default to `DNSClusterFirstWithHostNet` when
setting `spec.DNSPolicy` to true.

Author: nikhaild

controllers/object_controls.go

@@ -1696,12 +1696,14 @@ func TransformDCGMExporter(obj *appsv1.DaemonSet, config *gpuv1.ClusterPolicySpe
 		if remoteEngine != "" && strings.HasPrefix(remoteEngine, "localhost") {
 			// enable hostNetwork for communication with external DCGM using localhost
 			obj.Spec.Template.Spec.HostNetwork = true
+			obj.Spec.Template.Spec.DNSPolicy = corev1.DNSClusterFirstWithHostNet
 		}
 	}
 	// set hostNetwork if specified for DCGM Exporter (if it is already enabled above,
 	// do not touch the value)
 	if config.DCGMExporter.IsHostNetworkEnabled() {
 		obj.Spec.Template.Spec.HostNetwork = true
+		obj.Spec.Template.Spec.DNSPolicy = corev1.DNSClusterFirstWithHostNet
 	}
 
 	setRuntimeClassName(&obj.Spec.Template.Spec, config, n.runtime)

controllers/transforms_test.go

@@ -168,6 +168,11 @@ func (d Daemonset) WithHostNetwork(enabled bool) Daemonset {
 	return d
 }
 
+func (d Daemonset) WithDNSPolicy(policy corev1.DNSPolicy) Daemonset {
+	d.Spec.Template.Spec.DNSPolicy = policy
+	return d
+}
+
 func (d Daemonset) WithHostPID(enabled bool) Daemonset {
 	d.Spec.Template.Spec.HostPID = enabled
 	return d
@@ -1301,7 +1306,7 @@ func TestTransformDCGMExporter(t *testing.T) {
 					{Name: "DCGM_REMOTE_HOSTENGINE_INFO", Value: "nvidia-dcgm:5555"},
 					{Name: "foo", Value: "bar"},
 				},
-			}).WithContainer(corev1.Container{Name: "dummy"}).WithPullSecret("pull-secret").WithRuntimeClassName("nvidia").WithHostNetwork(true),
+			}).WithContainer(corev1.Container{Name: "dummy"}).WithPullSecret("pull-secret").WithRuntimeClassName("nvidia").WithHostNetwork(true).WithDNSPolicy(corev1.DNSClusterFirstWithHostNet),
 		},
 		{
 			description: "transform dcgm exporter with hostNetwork disabled",
@@ -1363,6 +1368,42 @@ func TestTransformDCGMExporter(t *testing.T) {
 				},
 			}).WithContainer(corev1.Container{Name: "dummy"}).WithPullSecret("pull-secret").WithRuntimeClassName("nvidia").WithHostNetwork(false),
 		},
+		{
+			description: "transform dcgm exporter with dcgm running on the host itself(DGX BaseOS)",
+			ds: NewDaemonset().
+				WithContainer(corev1.Container{
+					Name: "dcgm-exporter",
+					Env:  []corev1.EnvVar{{Name: "DCGM_REMOTE_HOSTENGINE_INFO", Value: "localhost:5555"}},
+				}).
+				WithContainer(corev1.Container{Name: "dummy"}),
+			cpSpec: &gpuv1.ClusterPolicySpec{
+				DCGM: gpuv1.DCGMSpec{
+					Enabled: newBoolPtr(false),
+				},
+				DCGMExporter: gpuv1.DCGMExporterSpec{
+					Repository:       "nvcr.io/nvidia/cloud-native",
+					Image:            "dcgm-exporter",
+					Version:          "v1.0.0",
+					ImagePullPolicy:  "IfNotPresent",
+					ImagePullSecrets: []string{"pull-secret"},
+					Args:             []string{"--fail-on-init-error=false"},
+					Env: []gpuv1.EnvVar{
+						{Name: "DCGM_REMOTE_HOSTENGINE_INFO", Value: "localhost:5555"},
+						{Name: "foo", Value: "bar"},
+					},
+				},
+			},
+			expectedDs: NewDaemonset().WithContainer(corev1.Container{
+				Name:            "dcgm-exporter",
+				Image:           "nvcr.io/nvidia/cloud-native/dcgm-exporter:v1.0.0",
+				ImagePullPolicy: corev1.PullIfNotPresent,
+				Args:            []string{"--fail-on-init-error=false"},
+				Env: []corev1.EnvVar{
+					{Name: "DCGM_REMOTE_HOSTENGINE_INFO", Value: "localhost:5555"},
+					{Name: "foo", Value: "bar"},
+				},
+			}).WithContainer(corev1.Container{Name: "dummy"}).WithPullSecret("pull-secret").WithRuntimeClassName("nvidia").WithHostNetwork(true).WithDNSPolicy(corev1.DNSClusterFirstWithHostNet),
+		},
 		{
 			description:      "transform dcgm exporter, openshift",
 			openshiftVersion: "1.0.0",