IPv6 Neighbor Discovery Suppression
In a data center fabric, you can
suppress Neighbor Discovery (ND) to help reduce ND control traffic.
![Note](images/note.png)
Note
ND suppression is supported on VLANs
and bridge domains.
By default, ND is not suppressed, which
can lead to excess control traffic.
- A device needs to forward traffic to an IP
address, but the corresponding MAC address is not in its ND cache.
- The device broadcasts an ND request
throughout the IP fabric.
When ND is suppressed, excess control
traffic is reduced.
- A device needs to forward traffic to an
IP address, but the corresponding MAC address is not in its ND cache.
- The device broadcasts an ND request.
- The leaf BGP EVPN control plane
intercepts the request and looks for a match in its local cache.
- If there is a match, the
control plane responds only to the device.
- If there is no match, the leaf
control plane broadcasts the request to the entire IP fabric.
![Tip](images/tip.png)
Tip
When the static anycast
gateway feature is enabled in an IP fabric, suppress ND on the respective VLANs or BDs
to prevent ND broadcast across the network.