A customer is undergoing a WAN re-architecture and wants to design QoS policies for remote sites that have low bandwidth. What must be considered to have CBWFQ configured in the parent and child…

When implementing a hierarchical QoS policy with CBWFQ (Class-Based Weighted Fair Queuing) at both parent and child levels, traffic policing is often required in the child policy to prevent traffic from exceeding its allocated bandwidth within the child policy and potentially starving other classes within the parent policy. Without policing, oversubscribed child classes could consume more than their fair share when aggregated.

CBWFQ can be supported in both parent and child policies when designing hierarchical QoS, given proper configuration considerations.

CBWFQ can be supported in both parent and child policies; it is not limited to only the parent.

While traffic shaping is typically configured on the parent policy to control the aggregate outbound traffic rate on an interface, it is not a requirement for having CBWFQ in both parent and child policies in the same way policing helps manage oversubscription within the hierarchy.