QOS on 6509/how do u know its working???

Unanswered Question
Apr 8th, 2008
User Badges:

I have a 6509 w sup720-10Ge and all am trying to do is have a separate voice and data queue on an uplink (which is just a gigport on a WS-X6748-GE-TX)

Again, all i want to do is have 2 queues..one for voice/one for data and trust the 46 markings coming from the lan on the other side (which is setup)

So I did this:

mls qos map dscp-cos 46 to 5

int g7/3

wrr-queue bandwidth 30 30 30

wrr-queue queue-limit 40 30 30

mls qos trust dscp

priority-queue cos-map 1 5

And the switch told me this when doing it:

switch#(config-if)# priority-queue cos-map 1 5

Propagating cos-map configuration to: Gi7/1 Gi7/2 Gi7/3 Gi7/4 Gi7/5 Gi7/6 Gi7/7

Gi7/8 Gi7/9 Gi7/10 Gi7/11 Gi7/12

But then I look at the config and the priority-queue cos map dissapeared from the interface config i put it on

I so much wish you can just put a "service-policy output" on the interface but it is not supported so you have to play with this wrr stuff with a priority queue and you cant even tell if its working or not..

Anyone do anything similar?

Again, just trying to preserve the DSCP46 markings coming into the switch and then queueing it outbound so it takes priority over the other (DSCP0,XYZ) traffic when there is congestion on the port.

Also, it seems you have to put in at least 3 "Wrr queue bandwidth" statements on this switch when every example i see only shows you need two; must be code or hardware

Thanks for any help

  • 1
  • 2
  • 3
  • 4
  • 5
Overall Rating: 0 (0 ratings)
schmij01 Tue, 04/08/2008 - 10:29
User Badges:

You can see the queuing strategy like this:

6500#sh queueing interface gi1/1

Interface GigabitEthernet1/1 queueing strategy: Weighted Round-Robin

Port QoS is enabled

Port is untrusted

Extend trust state: not trusted [COS = 0]

Default COS is 0

Queueing Mode In Tx direction: mode-cos

Transmit queues [type = 1p3q8t]:

Queue Id Scheduling Num of thresholds


01 WRR 08

02 WRR 08

03 WRR 08

04 Priority 01

You see that queue 4 is the priority queue. Further output from that command will show you that CoS 5 is mapped into queue 4. That tells you that all the proper configurations are there.

I believe that the default configuration is to have CoS 5 mapped to queue 4 as a priority queue, thus it doesn't show up in the config and your configuration commands are redundant. You need to know the right show command to see it configured.

afilandro Tue, 04/08/2008 - 12:11
User Badges:

Thanks for the command!

Yes you are absolutely correct! We just ran into the same thing on a 4507 in which I kept typing in

"Qos map dscp 46 to tx-queue 3"

and the thing kept disappearing from the config...go figure, its a default command :))

Thanks again!



This Discussion