A Cisco ACI environment consists of multiple silent hosts that are often relocated between leaf switches. When the host is relocated, the bridge domain takes more than a few seconds to relearn the…

Setting Unicast Routing to Enabled primarily concerns L3 forwarding within the bridge domain and does not directly address the speed of L2 host MAC address relearning for relocated silent hosts.

Enabling ARP Flooding in a bridge domain ensures that the ACI fabric floods all ARP requests and replies, rather than relying on hardware proxy or unicast routing for ARP resolution. This proactive flooding helps the fabric quickly discover and update the location of silent hosts that relocate, minimizing the impact of host mobility on the bridge domain's learning process.

Setting L2 Unknown Unicast to Hardware Proxy means the fabric will query the spine proxies for unknown unicast MAC addresses, which can introduce delay in learning new host locations, especially for silent hosts.

Configuring IP Data-Plane Learning to No would prevent the fabric from learning IP addresses from data plane traffic, which would hinder, not help, the fabric's ability to quickly track host locations.