diff --git a/pkg/beaconfqdn/mongodb.go b/pkg/beaconfqdn/mongodb.go
index 193872ec..8b23ec61 100644
--- a/pkg/beaconfqdn/mongodb.go
+++ b/pkg/beaconfqdn/mongodb.go
@@ -49,6 +49,7 @@ func (r *repo) CreateIndexes() error {
 	// set desired indexes
 	indexes := []mgo.Index{
 		{Key: []string{"-score"}},
+		{Key: []string{"src", "fqdn", "src_network_uuid"}, Unique: true},
 		{Key: []string{"src", "src_network_uuid"}},
 		{Key: []string{"fqdn"}},
 		{Key: []string{"-connection_count"}},