Sequence of QoS Actions

Explanation.

The correct sequence of QoS actions taken on egress traffic on the Cisco Nexus 7000 Series Switches is:

C. classification, marking, policing, queuing and scheduling, mutation.

1. Classification: Traffic is classified into different classes based on various criteria such as IP precedence, DSCP, CoS, source/destination IP addresses, and protocols. This is done using access control lists (ACLs), class maps, and policy maps.

2. Marking: Once the traffic is classified, it is marked with a QoS label, such as a DSCP value or CoS value. This marking is done to prioritize traffic, provide differentiated services, and enable downstream devices to apply QoS policies.

3. Policing: Policing involves limiting the traffic flow to a certain rate or bandwidth. If the traffic exceeds the defined rate, it is either dropped or marked down. This is done to prevent congestion and ensure that critical traffic receives higher priority.

4. Queuing and scheduling: After the traffic has been classified, marked, and policed, it is placed in appropriate queues based on the QoS labels. The queues are serviced using different scheduling algorithms, such as weighted round-robin (WRR) or strict priority (SP), based on the QoS requirements.

5. Mutation: The final step is mutation, which involves modifying the QoS labels of the traffic as it leaves the switch. This is done to ensure that the downstream devices can understand and apply the QoS policies.

Therefore, option C, classification, marking, policing, queuing and scheduling, mutation, is the correct sequence of QoS actions taken on egress traffic on the Cisco Nexus 7000 Series Switches.