QOS for voice

bjornarsb · ‎09-25-2013

Hi.

Why do I see voice traffic on one router and not on another:

Class-map: VOICE (match-all)
          0 packets, 0 bytes
          30 second offered rate 0 bps, drop rate 0 bps
          Match: dscp ef (46)
          Priority: 25% (9900 kbps), burst bytes 247500, b/w exceed drops: 0

Class-map: VOICE (match-all)
          8816096 packets, 1917880834 bytes
          5 minute offered rate 0 bps, drop rate 0 bps
          Match: dscp ef (46)

It's the same service-policy on both routers.

regards

bjornarb

amabdelh · ‎09-25-2013

Can you provide more details, configuration? Show commands as well

Sent from Cisco Technical Support iPhone App

bjornarsb · ‎09-25-2013

Hi.

We assume that the voice traffic is marked at source.

Configuration:

!

class-map match-any BUSINESS

match access-group name MARK-BUSINESS

class-map match-all SHAPING

match any

class-map match-all VOICE

match dscp ef

!

policy-map QOS

class VOICE

priority percent 25

set dscp ef

class BUSINESS

bandwidth remaining percent 70

set dscp af31

class class-default

fair-queue

set dscp default

policy-map QOS_VRF_BRUKER

class SHAPING

shape average percent 100

bandwidth percent 99

service-policy QOS

!

interface GigabitEthernet0/1

service-policy output QOS_VRF_BRUKER

!

amabdelh · ‎09-25-2013

bjornarb

few comments here:

- The policy-map on the second router it looks it is not configured correctly, I dont see the priority in there

- Why do re mark the packet in your policy if it is already marked? no need for the command "set dscp ef"

- clear the counters and change the load-interval to 30 seconds on both switches, run voice traffic or use ping command with extended option and set the TOS to 184, and provide the show policy-map from both routers. I see the rate in both routers is zero, lets verify there are marked packet with this dscp

Regards

bjornarsb · ‎09-25-2013

Hi again.

We removed the re-marking. Pinged with tos 184, but still no counters:

Class-map: VOICE (match-all)

0 packets, 0 bytes

30 second offered rate 0 bps, drop rate 0 bps

Match: dscp ef (46)

Priority: 25% (9900 kbps), burst bytes 247500, b/w exceed drops: 0

amabdelh · ‎09-25-2013

Can you provide the complete output?

is the traffic matching the class-default?

bjornarsb · ‎09-25-2013

#sh policy-map interface gigabitEthernet 0/1
GigabitEthernet0/1

Service-policy output: QOS_VRF_BRUKER

    Class-map: SHAPING (match-all)
      396310 packets, 50532155 bytes
      30 second offered rate 751000 bps, drop rate 0 bps
      Match: any
      Queueing
      queue limit 64 packets
      (queue depth/total drops/no-buffer drops) 0/0/0
      (pkts output/bytes output) 396310/50538173
      shape (average) cir 40000000, bc 400000, be 400000
      target shape rate 40000000
      bandwidth 99% (39600 kbps)

Service-policy : QOS

        queue stats for all priority classes:

          queue limit 64 packets
          (queue depth/total drops/no-buffer drops) 0/0/0
          (pkts output/bytes output) 0/0

        Class-map: VOICE (match-all)
          0 packets, 0 bytes
          30 second offered rate 0 bps, drop rate 0 bps
          Match: dscp ef (46)
          Priority: 25% (9900 kbps), burst bytes 247500, b/w exceed drops: 0

        Class-map: BUSINESS (match-any)
          396219 packets, 50522352 bytes
          30 second offered rate 751000 bps, drop rate 0 bps
          Match: access-group name MARK-BUSINESS
            396219 packets, 50522352 bytes
            30 second rate 751000 bps
          Queueing
          queue limit 64 packets
          (queue depth/total drops/no-buffer drops) 0/0/0
          (pkts output/bytes output) 396219/50528370
          bandwidth remaining 70% (20790 kbps)
          QoS Set
            dscp af31
              Packets marked 396219

        Class-map: class-default (match-any)
          91 packets, 9803 bytes
          30 second offered rate 0 bps, drop rate 0 bps
          Match: any
          Queueing
          queue limit 64 packets
          (queue depth/total drops/no-buffer drops/flowdrops) 0/0/0/0
          (pkts output/bytes output) 91/9803
          Fair-queue: per-flow queue limit 16
          QoS Set
            dscp default
              Packets marked 0

    Class-map: class-default (match-any)
      0 packets, 0 bytes
      30 second offered rate 0 bps, drop rate 0 bps
      Match: any

      queue limit 64 packets
      (queue depth/total drops/no-buffer drops) 0/0/0
      (pkts output/bytes output) 0/0

bjornarsb · ‎09-25-2013

Here is the output after 20 ping with TOS 184.

Service-policy : QOS

        Class-map: VOICE (match-all)
          20 packets, 2360 bytes
          5 minute offered rate 1000 bps, drop rate 0 bps
          Match: dscp ef (46)
          Queueing
            Strict Priority
            Output Queue: Conversation 264
            Bandwidth 25 (%)
            Bandwidth 10000 (kbps) Burst 250000 (Bytes)
            (pkts matched/bytes matched) 0/0
            (total drops/bytes drops) 0/0

bjornarsb · ‎09-26-2013

The problem was that if you have auto qos on trunk ports it will remove the marking if you do not have qos on access ports.