A QoS profile is configured as shown in the image. The following throughput is realized:
Class 3 traffic 325Mbps -
Class 5 traffic 470Mbps -
Class 7 traffic: 330Mbps -
What happens as a result?
A QoS profile is configured as shown in the image. The following throughput is realized:
Class 3 traffic 325Mbps -
Class 5 traffic 470Mbps -
Class 7 traffic: 330Mbps -
What happens as a result?
In a QoS profile, when contention occurs, traffic assigned a lower priority is more likely to be dropped. In this scenario, the combined traffic of Class 3, Class 5, and Class 7 exceeds the maximum egress of 1000 Mbps. Since Class 7 has the lowest priority among these three classes, it will experience the most packet drops in favor of maintaining the Egress Guaranteed throughput for Classes 3 and 5, which have higher priorities. This ensures that higher priority traffic is less affected when the total traffic exceeds the available bandwidth.
B • Priority—Click and select a priority to assign it to a class: ◦ real-time ◦ high ◦ medium ◦ low When contention occurs, traffic that is assigned a lower priority is dropped. Real-time priority uses its own separate queue.
A: Egress Guaranteed—The amount of bandwidth guaranteed for matching traffic. When the egress guaranteed bandwidth is exceeded, the firewall passes traffic on a best-effort basis. Bandwidth that is guaranteed but is unused continues to remain available for all traffic. Depending on your QoS configuration, you can guarantee bandwidth for a single QoS class, for all or some clear text traffic, and for all or some tunneled traffic. Example: Class 1 traffic has 5 Gbps of egress guaranteed bandwidth, which means that 5 Gbps is available but is not reserved for class 1 traffic. If Class 1 traffic does not use or only partially uses the guaranteed bandwidth, the remaining bandwidth can be used by other classes of traffic. However, during high traffic periods, 5 Gbps of bandwidth is absolutely available for class 1 traffic. During these periods of congestion, any Class 1 traffic that exceeds 5 Gbps is best effort https://docs.paloaltonetworks.com/pan-os/9-1/pan-os-admin/quality-of-service/qos-concepts/qos-bandwidth-management
Answer B: 325+470+330 > 1000 Egress Max
It is not A, because the total max egress is defined as 1,000 and the sum of the three kinds of traffic is bigger than that. B is the correct answer, due to the priority they have assigned, 7 being "low" priority.
Leaning heavily towards B. I believe A to be a fact, but the sum of the guaranteed max per class for all classes is already greater than 1000 ( the configured global max) so the fw will start dropping packets and class 7 will lose most of them according to priority. Basically, B is a "better" correct answer for this question than A
I think B is correct
The given image depicts that all the classes have already exceeded their bandwidth which translates to traffic 3,5, and 7 dropping more traffic compared to other classes.
I'm leaning towards B. Here's why: A seems irrelevent. The question is about classes 3,5, and 7. They're exceeding their guaranteed througput, so this doesnt really apply. B is accurate. 7 will have more drops as it's a lower priority. Although I believe this would only be dropped in times of congestion since the traffic above the guaranteed bandwidth is still forwarded as best effort. C isnt accurate. Egress max is the most a class can forward. This makes it sound as if guaranteed or not. D Nothing is hitting the egress max so this seems irrelevant.
B as per @confusion
Should be C. All classes should be able to use available unused bandwidth, as far as it doesn't reach their MAX yet.
Should be B, no unused bandwidth, the 3 classes already exceeded the interface maximum so QoS will kick in