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QOS at Layer 3

grichardson661
Level 1
Level 1

Hi,

I have a question regarding QOS. Consider the following topology - IP-Phone > 2960 > 2x10Gb up to > 3850.

The IP Phone is obtaining its Cos 5 and DSCP 46 markers from the local DHCP server, all good there.

When making a VoIP call i can see the traffic falling into the correct queues on the 2960 as below, all good there.

 

GigabitEthernet1/0/1 (All statistics are in packets)

dscp: incoming
-------------------------------

0 - 4 : 92871 0 0 0 0
5 - 9 : 0 0 0 0 0
10 - 14 : 0 0 0 0 0
15 - 19 : 0 0 0 0 0
20 - 24 : 0 0 0 0 115723
25 - 29 : 0 0 0 0 0
30 - 34 : 0 0 0 0 0
35 - 39 : 0 0 0 0 0
40 - 44 : 0 0 0 0 0
45 - 49 : 0 4653 0 0 0
50 - 54 : 0 0 0 0 0
55 - 59 : 0 0 0 0 0
60 - 64 : 0 0 0 0
dscp: outgoing
-------------------------------

0 - 4 : 221207 0 0 0 0
5 - 9 : 0 0 0 0 0
10 - 14 : 0 0 0 0 0
15 - 19 : 0 0 0 0 0
20 - 24 : 0 0 0 0 0
25 - 29 : 0 0 0 0 0
30 - 34 : 0 0 0 0 0
35 - 39 : 0 0 0 0 0
40 - 44 : 0 0 0 0 0
45 - 49 : 0 0 0 0 0
50 - 54 : 0 0 0 0 0
55 - 59 : 0 0 0 0 0
60 - 64 : 0 0 0 0
cos: incoming
-------------------------------

0 - 4 : 150720 0 0 115723 0
5 - 7 : 4653 0 0
cos: outgoing
-------------------------------

0 - 4 : 242373 0 41 0 29
5 - 7 : 0 16 1202357
output queues enqueued:
queue: threshold1 threshold2 threshold3
-----------------------------------------------
queue 0: 0 0 0
queue 1: 0 465783 1208385
queue 2: 0 0 220924
queue 3: 0 0 0

Now when the traffic hits the 3850 the packets do not seem to be falling into the correct polices based around the classification below:

3850#show policy-map interface tenGigabitEthernet 1/0/1 out
TenGigabitEthernet1/0/1

Service-policy output: AutoQos-4.0-Output-Policy

queue stats for all priority classes:
Queueing
priority level 1

(total drops) 0
(bytes output) 190555460

Class-map: AutoQos-4.0-Output-Priority-Queue (match-any)
0 packets
Match: dscp cs4 (32) cs5 (40) ef (46)
0 packets, 0 bytes
5 minute rate 0 bps
Match: cos 5
0 packets, 0 bytes
5 minute rate 0 bps
Priority: 30% (3000000 kbps), burst bytes 75000000,

I can see a total of 190555460 bytes in the priority level 1 queue but where the class map shows Match: dscp cs4 (32) cs5 (40) ef (46), i would have thought these counters would have been increased, is this normal? Or is this because the ports/switch is not under congestion and packets are sent as normal with no QOS or queuing applied?

Cheers

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