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New Member

Help understanding qos settings

Im trying to get a deeper understanding of the QoS settings on a 6509 port. I pulled the following from a port that the port QoS settings were populated with AutoQoS:

switchport trunk encapsulation dot1q

switchport mode trunk


wrr-queue bandwidth 50 255

wrr-queue queue-limit 75 15

wrr-queue random-detect min-threshold 2 70 100

wrr-queue random-detect max-threshold 2 90 100

wrr-queue cos-map 1 2 0

wrr-queue cos-map 2 1 1 2 3 4

wrr-queue cos-map 2 2 6 7

rcv-queue cos-map 1 1 0

rcv-queue cos-map 1 3 1 2 3 4

rcv-queue cos-map 1 4 6 7

mls qos trust cos

auto qos voip trust

Based on the commands above, i believe the following is happening:

1. Q1 T2 - CoS 0 packets

2. Q2 T1 - Cos 1,2,3,4 packets

3. Q2 T2 - Cos 6,7 packets

4. Q2 is being weighted at 255, Q1 at 50 (Q2 is given more priority)

This port supports 2q2t

Can somebody help me understand what is happening to packets with a CoS of 5 (voice)? How are they getting priority above other packets in the above config?

New Member

Re: Help understanding qos settings

I kind of answered my own question...the port is actually a 1p2q2t for transmit.

I did a:

show queuing int gx/x

That was showing me that CoS 5 is mapped to q3t1, which must be the priority queue. So im assuming that is a default setting.