A Layer 2 Cisco FabricPath multipoint processor network requires more bandwidth. How can you reduce the oversubscription ratio for the edge ports in the network design?

Adding leaf switches increases the total number of edge ports and their aggregate bandwidth, which raises the numerator of the oversubscription ratio and makes the problem worse rather than better.

Oversubscription ratio equals total edge port bandwidth divided by aggregate uplink bandwidth toward the spine; adding spine switches creates additional equal-cost uplink paths from each leaf, increasing the uplink bandwidth denominator and reducing the ratio. FabricPath supports ECMP across all spine uplinks simultaneously, so each additional spine device actively carries traffic and contributes to the reduction.

Enabling vPC+ allows FabricPath edge nodes to present a single logical port channel to dual-homed hosts for redundancy and loop prevention, but it does not add uplink capacity to the spine tier and does not affect the oversubscription ratio.

ECMP distributes existing traffic across available equal-cost paths to improve link utilization balance, but it does not provision additional physical bandwidth and therefore cannot change the oversubscription ratio.