Hello ,
Normally vPC are been designed if you have high bandwidth or Multi ether channel requirement for servers.
With vPC between Aggregation and Access layer is used for using all available link bandwidth with loop free topology. Which gives fast convergence along with link level resiliency and it eliminates stp blocked ports for ensuring high availability.
As you know a virtual PortChannel (vPC) allows links that are physically connected to two different Cisco Nexus Family devices to appear as a single PortChannel to a third device.
The third device can be a switch, server, or any other networking device that supports EtherChannel. A vPC can provide Layer 2 multipathing, which allows you to create redundancy by increasing bandwidth, enabling multiple parallel paths between nodes and traffic load balancing in cases in which alternative paths exist.
Hope it Helps..
-GI
