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New Member

simple qos config

Hi all, is there a simple qos config I can type for simply trusting ip traffic from my phone ?


Re: simple qos config

It will depend on your IOS version and hardware type.

Auto QoS feature is available in certain platform/IOS version.

New Member

Re: simple qos config

I would suggest Auto QOS it is easy and I have used it on my switch port, you can set ip up to trust VoIP or use a basic auto qos trust. look through the doc's below. HTH

interface FastEthernet0/3

switchport access vlan 222

switchport mode dynamic desirable

switchport voice vlan 698

speed 100

duplex full

srr-queue bandwidth share 10 10 60 20

srr-queue bandwidth shape 10 0 0 0

priority-queue out

mls qos trust device cisco-phone

mls qos trust cos

auto qos voip cisco-phone

spanning-tree portfast

New Member

Re: simple qos config

what command would i put on the trunk uplink ports?



New Member

Re: simple qos config


auto qos voip trust

This enables auto-QoS on the interface, and specify that the interface is connected to a trusted router or switch.

New Member

Re: simple qos config

hi there

when you put in the cisco-phone command, what is it looking for? would it work with other phone vendors?

what do these commands mean?

mls qos trust device cisco-phone ?

mls qos trust cos ?

auto qos voip cisco-phone ?

New Member

Re: simple qos config

mls qos trust device cisco-phone =

Trust marking only from a cisco IP phone (The switch uses cdp to know a cisco phone is plugged into the port).

mls qos trust cos =

This command instructs the switchport to trust class of service (cos) markings originating from the device plugged into the port.

auto qos voip cisco-phone =

This command enables / starts auto qos on the switch port and tells the switch to place commands that trust markings only from a cisco phone.

Cisco devices use CDP (cisco discovery protocol) to detect each other. For non cisco devices you will have to configure how you want the trust to be established.

By default cisco IP phone will mark voice traffic as 5. So say for instane I want to mark a COS from a device you could say

mls qos trust cos

switchport priority extend cos 5

The second command will mark traffic from the phone with cos 5 which is recommended for voice traffic. There is more to COS. This is the tip of the iceberg.

Pls rate if helpful.