diff --git a/docs/network/default_cni_plugin.md b/docs/network/default_cni_plugin.md
index 0b2da40e48..363c2d955b 100644
--- a/docs/network/default_cni_plugin.md
+++ b/docs/network/default_cni_plugin.md
@@ -81,6 +81,7 @@ ovsInit:
   externalGatewayInterface: eth1
 mtu: 1300
 ```
+**NOTE:* The change of `mtu` configuration in `ovn.yaml` requires node reboot to take effect. <br>
 
 ### Configuring Host