auto qos on uplinks?

[billmatthews]

We have a stack of 2960s at our access layer, connecting up (via a pair of fibers in a port channel) to our 3750x at the core. 

We will have Cisco VoIP phones connecting to the access layer.  So for each switchport I've used auto qos voip cisco-phone.  But for the uplink ports do I need any QoS?  I would imagine I do at least need trust, but I can't seem to use auto qos on the uplink ports (says it's not valid on a trunk).

Do I need to configure any QoS, either on the physical uplink interfaces or on the Port Channel?

Thanks,

Bill

[Karsten Iwen]

If you enforce QoS on the access-Layer, then you should just trust the DSCP-settings coming in on your Uplinks and activate the priority-queues on the ports. That can also be done with auto-qos:

switch(config-if)#   auto qos trust dscp

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[billmatthews]

The problem is there are members of a port channel...

(config-if)#auto qos trust dscp

AutoQoS Error: AutoQoS can not be configured on member port(s) of a port-channel

[Karsten Iwen]

ok, if the switch doesn't like auto qos, then i would use the "native" commands:

interface range Gig1/0/1 -2

  mls qos trust dscp

  queue-set 2

  priority-queue out

(That assumes that auto qos is used on other ports so that the queue-set 2 and other things are already set)

@Amrinder: The capability to trust COS or DSCP has nothing to do with the settings of the interface as L2- or L3-Port. It's just a decision which information is more trustworthy in a given situation.

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[michalweiss]

Hello Karsten,

I have a similar issue. Interfaces 1-48 are user facing with the following configuration.

description USER_PORTS
switchport access vlan 10
switchport mode access
switchport voice vlan 20
logging event link-status
srr-queue bandwidth share 1 30 35 5
priority-queue out
mls qos trust device cisco-phone
mls qos trust cos
auto qos voip cisco-phone
spanning-tree portfast
spanning-tree bpduguard enable
service-policy input AUTOQOS-SRND4-CISCOPHONE-POLICY

and I am not sure how to configure my uplink ports that are in a channel group. 

switchport trunk encapsulation dot1q
switchport trunk native vlan 998
switchport trunk allowed vlan 5,10,20
switchport mode trunk
logging event trunk-status
channel-group 45 mode active

CW-SW-PP1-3750#sh mls qos queue-set
Queueset: 1
Queue : 1 2 3 4
----------------------------------------------
buffers : 15 25 40 20
threshold1: 100 125 100 60
threshold2: 100 125 100 150
reserved : 50 100 100 50
maximum : 200 400 400 200
Queueset: 2
Queue : 1 2 3 4
----------------------------------------------
buffers : 25 25 25 25
threshold1: 100 200 100 100
threshold2: 100 200 100 100
reserved : 50 50 50 50
maximum : 400 400 400 400

Do I just need to send the 

mls qos trust dscp

  queue-set 2

  priority-queue out

commands to the uplink ports? 

[singhaam007]

Hi Bill,

You can use Auto Qos trust cos if the interface is layer 2 but use Auto Qos trust DSCP for layer 3 interface.

Try Auto qos trust on your uplink

thanks