diff --git a/buf.gen.yaml b/buf.gen.yaml
index 27d3e8d580d69c639e760c2704ea4f1d84b35d0b..cded753483a2dc1d09d87a8db48bba403092cc9b 100644
--- a/buf.gen.yaml
+++ b/buf.gen.yaml
@@ -14,3 +14,6 @@ plugins:
       - paths=source_relative
   - remote: buf.build/grpc-ecosystem/plugins/openapiv2:v2.6.0-1
     out: openapiv2
+    opt:
+      - allow_merge=true
+      - merge_file_name=gosdn_northbound