On a 3750 enhanced services port, are hierarchical queueing and standard queuing features mutually exclusive?

Question

When you configure hierarchical queueing on an enhanced services port, should one also configure the egress queue chararcteristics such as buffer space and thresholds, shaped/shared weights, egress priority queue, etc., that is all of those characteristics that one would configure if one were configuring a port for standard QOS.  In other words, on an enhanced services port, are the hierarchical queueing features using the modular QOS CLI and the standard egress queueing features supposed to be used together or are they mutually exclusive?

Answer 1

Hi Christine,
Answer to your confusion is in the following document.
http://www.cisco.com/en/US/docs/switches/metro/catalyst3750m/software/release/12.1_14_ax/release/notes/OL464603.html#wp58682
On an ES port, you can use LLQ (enabled with the priority policy-map class configuration command) and the egress priority queue (enabled with the priority-queue out
interface configuration command). By using these two features, you can
give priority to a class of traffic and avoid losing traffic when the
switch is congested. In previous releases (before the egress priority
queue was supported), you could put a traffic class into the
strict-priority queue, but congestion at the egress queue-sets could
result in the dropping of that priority traffic. The priority-queue out
interface configuration command enables you to prioritize the same
traffic class at the egress queue-sets, ensuring that priority traffic
reaches the hierarchical queues and is processed with priority.
you can also fine tune the Queue-sets for your desired results.
http://www.cisco.com/en/US/docs/switches/metro/catalyst3750m/software/release/12.2_50_se/configuration/guide/swqos.html#wp1162303