3750 qos on routed interface

[gshonting]

I have 2 3750G-24 as the core of my voice/data network. I have 2 vlans (voice,data) and it seems like when I cross the routed interfaces (virtual vlanX interfaces) I lose my qos tagging. I have tried route-maps and policy maps but they are not working (the policy maps are not supported on virtual interfaces)

Anyone with a solution?? I have searched cisco.com and unless i am blind, have not found what I am looking for.

[a.awan]

When you say you are losing your qos tagging do you mean DSCP or just CoS tags?

[gshonting]

I know that I am definitely losing the DSCP values. I can't tell if I am losing CoS tags, I don't think the sniffer is picking them up.

Here is the DLC header-

00 08 0d cf 9c 0b 00 0f 8f 19 b3 c1 08 00

My problem is that we are using IP communicators (softphone) on laptops on the data vlan and connecting to gateways and other phones on the voice vlan. We are having alot of voice quality issues even on the local lan and I want to make sure QoS/CoS is being carried all the way through the LAN.

[a.awan]

So lets take the example of a soft phone connected to an edge switch. How have you configured classification based on which you assign DSCP? Are you trust cos or dscp tags generated by the edge device or have you configured your own QoS ACLs to assign DSCP based on custom criteria?

[gshonting]

Here is the edge switchport config-

End user port-----

interface FastEthernet0/1

switchport access vlan 50

switchport trunk encapsulation dot1q

switchport trunk native vlan 50

switchport mode trunk

switchport voice vlan 10

mls qos trust device cisco-phone

mls qos trust cos

auto qos voip cisco-phone

wrr-queue bandwidth 20 1 80 1

wrr-queue min-reserve 1 5

wrr-queue min-reserve 2 6

wrr-queue min-reserve 3 7

wrr-queue min-reserve 4 8

wrr-queue cos-map 1 0 1 2 4

wrr-queue cos-map 3 3 6 7

wrr-queue cos-map 4 5

priority-queue out

spanning-tree portfast

Gigabit uplink port------------

interface GigabitEthernet0/1

switchport trunk encapsulation dot1q

switchport mode trunk

mls qos trust cos

auto qos voip trust

wrr-queue bandwidth 20 1 80 1

wrr-queue queue-limit 80 1 20 1

wrr-queue cos-map 1 0 1 2 4

wrr-queue cos-map 3 3 6 7

wrr-queue cos-map 4 5

priority-queue out

end

Here is the core switch-

interface GigabitEthernet1/0/24

switchport trunk encapsulation dot1q

switchport mode trunk

srr-queue bandwidth share 10 10 60 20

srr-queue bandwidth shape 10 0 0 0

mls qos trust cos

no mdix auto

auto qos voip trust

end

Core Vlan Interfaces----

interface Vlan1

no ip address

!

interface Vlan2

description Data Vlan

ip address 10.199.0.29 255.255.252.0

!

interface Vlan10

description Voice Vlan

ip address 10.199.10.1 255.255.255.0

All of the qos settings are a result of using Auto QoS

[a.awan]

The problem could be that the softphone application is not marking the voice packets with the correct CoS. Another issue could be that you switch port is resetting the CoS received from the PC as you have established a trust boundary that basically looks for an attached ip phone and if it does not find it, it basically does not trust any CoS markings. For one particular interface try applying a policy map and explicitly set the DSCP to 45 and see if that works. You mentioned you have tried to do that but how did you approach it?

[nz-ipv6]

Hi there,

I would suggest upgrading IOS on your switch.The IOS supports now autoqos command for softphone and you can apply it on your edge port.

Here is the brief output from config guide 12.2(20)SE

If you entered the auto qos voip cisco-softphone command,

the switch automatically creates class maps and policy maps.

Switch(config)# mls qos map policed-dscp 24 26 46 to

0

Switch(config)# class-map match-all

AutoQoS-VoIP-RTP-Trust

Switch(config-cmap)# match ip dscp ef

Switch(config)# class-map match-all

AutoQoS-VoIP-Control-Trust

Switch(config-cmap)# match ip dscp cs3 af31

Switch(config)# policy-map AutoQoS-Police-SoftPhone

Switch(config-pmap)# class AutoQoS-VoIP-RTP-Trust

Switch(config-pmap-c)# set ip dscp ef

Switch(config-pmap-c)# police 320000 8000

exceed-action policed-dscp-transmit

Switch(config-pmap)# class

AutoQoS-VoIP-Control-Trust

Switch(config-pmap-c)# set ip dscp cs3

Switch(config-pmap-c)# police 32000 8000

exceed-action policed-dscp-transmit

After creating the class maps and policy maps, the switch

automatically applies the policy map called

AutoQoS-Police-SoftPhone to an ingress interface on which

auto-QoS with the Cisco SoftPhone feature is enabled.

Switch(config-if)# service-policy input

AutoQoS-Police-SoftPhone

Cheers

Trib

[Aaron Dhiman]

Hi, a few questions:

1. Why is there no "priority-queue out" on the core switch?

2. Why does the core switch go to "srr-queue" instead of "wrr-queue"

3. Why on the end-user/phone port is queue 4 not give '0' weight? "wrr-queue bandwidth 20 1 80 1"

(I thought it should be more like "wrr-queue bandwidth 10 20 70 0" to make the queue 4 PQ)