A Cisco ACI bridge domain and VRF are configured with a default data-plane learning configuration.

In a Cisco ACI bridge domain and VRF configured with a default data-plane learning configuration, the two endpoint attributes that are programmed in the leaf switch when receiving traffic are:

Local MAC, IP (Option D)5.

Local Subnet (Option E)5. These attributes are learned by the ACI fabric through common network methods such as ARP, GARP, and ND, as well as through the data-plane. The local MAC and IP addresses are learned and used for traffic routing and bridging, while the local subnet information is used for traffic optimization and endpoint location tracking56.