Don't report VLAN interfaces as oper_down

src/sonic_ax_impl/mibs/ietf/rfc1213.py

@@ -530,7 +530,12 @@ def get_oper_status(self, sub_id):
         :param sub_id: The 1-based sub-identifier query.
         :return: oper state value for the respective sub_id.
         """
-        return self._get_status(sub_id, "oper_status")
+        if self.get_oid(sub_id) in self.vlan_oid_name_map:
+            # VLAN interfaces don't have an operational status, so return admin status for them
+            key = "admin_status"
+        else:
+            key = "oper_status"
+        return self._get_status(sub_id, key)
 
     def get_mtu(self, sub_id):
         """