diff --git a/doc/netplan-yaml.md b/doc/netplan-yaml.md
index b22755755..7d13362fb 100644
--- a/doc/netplan-yaml.md
+++ b/doc/netplan-yaml.md
@@ -1573,6 +1573,7 @@ The specific settings for bonds are defined below.
     > Set whether to set all ports to the same MAC address when adding
     > them to the bond, or how else the system should handle MAC addresses.
     > The possible values are `none`, `active` and `follow`.
+    > This only works with specific bonding modes such as active-backup.
 
   - **`gratuitous-arp`** (scalar)