diff --git a/etc/neutron.conf b/etc/neutron.conf
index aedc0fa988..d0ab46d48f 100644
--- a/etc/neutron.conf
+++ b/etc/neutron.conf
@@ -134,6 +134,9 @@ lock_path = $state_path/lock
 # Maximum number of fixed ips per port
 # max_fixed_ips_per_port = 5
 
+# Maximum number of routes per router
+# max_routes = 30
+
 # =========== items for agent management extension =============
 # Seconds to regard the agent as down; should be at least twice
 # report_interval, to be sure the agent is down for good