QoS port priority EOS

[Holger_Gmerek]

given the following configuration:

D2(su)->show cos state
Class-of-Service application is enabled

D2(su)->show cos settings
CoS Index Priority ToS IRL flood-ctrl
--------- ---------- ------- ------- ----------
0 0 * * enabled
1 1 * * enabled
2 2 * * enabled
3 3 104 * enabled
4 4 * * enabled
5 5 184 * enabled
6 6 * * enabled
7 7 * * enabled
D2(su)->show port priority ge.1.5
ge.1.5 is set to 3D2(su)->show port txq ge.1.5
Port Alg Q0 Q1 Q2 Q3 Q4 Q5 Q6 Q7
----- --- --- --- --- --- --- --- --- ---
ge.1.5 WRR 2 5 7 10 12 15 20 29

D2(su)->show port priority-queue ge.1.5
Port P0 P1 P2 P3 P4 P5 P6 P7
--------- -- -- -- -- -- -- -- --
ge.1.5 2 0 1 3 4 5 6 7

I would expect that untagged traffic ingressing in ge.1.5 will be assigned a priority of 3
and it will carry this when egressing as a tagged frame.
This behaviour was confirmed with wireshark; tagged frames egressing carry a priority of 3.

The question now is, does the traffic get to Q3 and is it forwarded according to the txq rules (10%) of all ???

Is there any way to confirm the COS configuration ??

Also ist it enough to have the ToS/CoS mapping in the cos settings to priorize AF31 and EF or ist policy a must at this stage ??
The devices are sending DSCP mared traffic, the PBX does not, thats the port priority conf.

TIA.

[Paul_Poyant]

You're welcome, Holger.
Yes, D2 / B5 / C5 Policy should work fine here, and the discussion is 97% similar for all.

[Holger_Gmerek]

Thanks Paul for your fast and detailed answer, as always.
So since i have Unify(Siemens) phones that mark their traffic with TOS/DSCP and not L2 priority i have to do the ToS/CoS mapping via policy upon ingress. Since i have also B5 and C5 i will not use the diffserv command set.

Thanks Holger

[Paul_Poyant]

Here's further discussion on the EOS "CoS confirmation / QoS testing" front...
how_to_test_a_quality_of_service_configuration

[Paul_Poyant]

The port txq settings represent the minimum guaranteed percentage of available Weighted Round Robin service (total = 100) that will be dedicated to that port's packet transmission, as needed.
The port priority-queue settings represent the actual hardware transmit queue number (for the D2, 0 through 7 exist) used for each of the possible packet priorities 0 through 7.
Here, these all appear to be set at their defaults.

"I would expect that untagged traffic ingressing in ge.1.5 will be assigned a priority of 3 and it will carry this when egressing as a tagged frame."
Yes, true - as you've determined.

"Does the traffic get to Q3 and is it forwarded according to the txq rules (10%) of all?"
Yes. But understand that it's only restricted to 10% if the higher-priority queues are demanding full attention. It's possible that in effect, Q3 could receive 100% of the service.

"Is there any way to confirm the COS configuration?"
As already stated, officially the answer here is No.

"Is it enough to have the ToS/CoS mapping in the cos settings to priorize AF31 and EF or is policy a must at this stage?"
By default, none of this examines or cares about the TOS/DSCP settings of incoming frames.
On the D2 without a Policy license, one could use Diffserv (outlined in Hub KB 5848, http://bit.ly/18F0WPL) to act upon DSCP settings.
On the D2 with a Policy license, one could use Policy (for example Hub KB 7589, http://bit.ly/18ffoh8) to act upon DSCP settings.

Questions?