Refer to the exhibit. Fiber links are provisioned directly between the spine and leaf switches in the given LAN topology. A /30 prefix has been configured over each fiber link to provide underlay conn

Configuring /30 links as OSPF point-to-point networks is standard for underlay routing but does not inherently provide the shortest possible convergence time for link failures without additional mechanisms like BFD.

Enabling Bidirectional Forwarding Detection (BFD) on the /30 links is the most effective action to achieve the shortest possible convergence time when a fiber link is cut. BFD is a lightweight protocol that provides rapid fault detection for forwarding paths (in milliseconds), allowing routing protocols (like OSPF or BGP) to be notified of a link failure almost instantly, leading to significantly faster convergence than relying solely on default hello timers.

UDLD (UniDirectional Link Detection) helps detect unidirectional links and prevent network issues but does not directly accelerate convergence time for link down events in the same way BFD does for routing protocols.

Configuring ECMP (Equal-Cost Multipath) enables traffic distribution over multiple equal-cost paths, improving bandwidth and resilience, but it's a load-balancing mechanism and does not directly speed up the detection of a link failure on one of those paths.