diff --git a/internal/collector/hyperv/hyperv_test.go b/internal/collector/hyperv/hyperv_test.go
index 254994ca..b18f4924 100644
--- a/internal/collector/hyperv/hyperv_test.go
+++ b/internal/collector/hyperv/hyperv_test.go
@@ -40,6 +40,10 @@ func TestCollector(t *testing.T) {
 	testutils.RequireFixtureMetric(t, metrics, hyperv.Name, "windows_hyperv_dynamic_memory_vm_physical_bytes", prometheus.Labels{"vm": "GitHubActions"})
 	testutils.RequireFixtureMetric(t, metrics, hyperv.Name, "windows_hyperv_vm_processor_count", prometheus.Labels{"vm": "GitHubActions"})
 
+	// An empty "Hyper-V DataStore" counter set is tolerated as an optional
+	// instance group, so require a series explicitly (#2328).
+	testutils.RequireFixtureMetric(t, metrics, hyperv.Name, "windows_hyperv_datastore_fragmentation_ratio", nil)
+
 	// The fixture VM is not replicated, but every VM has a primary replication relationship.
 	if metric := testutils.RequireFixtureMetric(t, metrics, hyperv.Name, "windows_hyperv_replica_vm_state", prometheus.Labels{"vm": "GitHubActions", "relationship": "primary"}); metric != nil {
 		require.InDelta(t, 0, metric.GetGauge().GetValue(), 0, "expected replication to be disabled")