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3 questions re QoS Setup VS-S2T-10G with WS-X68xx-SFP 15.0(1)SY1

The newer Sup 2T with WS-X6824-SFP (or WS-X6848-SFP) is behaving odd.

We are trying to ensure that we trust DSCP for our ingress policy and for specified traffic that it be placed in the proper priority queue for egress policy.

For ingress, it appears that the new default is to trust DSCP; but it doesn't seem to verify correctly.

For instance via a show queuing command on a relevant port I see:

Interface GigabitEthernet1/1/x queuing strategy: Weighted Round-Robin

Port QoS is enabled globally

Queuing on Gi1/1/21: Tx Enabled Rx Enabled

Trust boundary disabled

Trust state: trust DSCP

Trust state in queuing: trust COS

Extended trust state: not trusted [COS=0]

The first question is: is ingress really working for DSCP market traffic?  The trust state in queuing showing trust COS creates doubt.

For egress, we have reviewed CCO and are applying the following QoS configuration making DSCP CS5/EF traffic prioirty:

class-map type lan-queuing match-any c_map_cos_5

match cos 5

policy-map type lan-queuing p_map_1p3q8t

class c_map_cos_5


The second question is: IOS seems to only allow this to be applied to physical interfaces though it accepts it on etherchannel interfaces but it does not seem to apply correctly and to all member ports.  Is applying QoS egress policies to physical ports appropriate and not etherchannel?

The third and final question is if there is any value in setting up the remaining COS classes 0-4 and 6-7 as the examples in the 15.0SY software configuration guide shows as part of examples; but not with any good explanation.


class c_map_cos_6_7

bandwidth remaining percent 40

queue-buffers ratio 15

random-detect cos-based- aggregate