Answer:
The OSPF link cost uses to control the route routing, we can set it manually or automatically calculate.
The OSPF automatically calculates this cost according to the interface bandwidth. OSPF uses the formula: Cost of the interface = Bandwidth reference value/Interface bandwidth. The integer of the calculated result is the cost of the interface. If the calculated result is smaller than 1, the cost value is 1. Changing the bandwidth reference value can change the cost of an interface.
We can design the OSPF cost refers to the bandwidth. If the network has a link that is 100G, we can set the reference value as 10000M.
Thanks!