Qos Consistency

[DJames]

In my Lan environment I have a 3570-L3 distribution switch trunked to  2960 access switches.  If I want to enable QOS across my LAN with Cisco IP phones connected to 2970 switches would not the auto qos command that I activate on my 3570 also be the same qos command that would be activated on the 2970?  Simply stating, is the QOS policies, class-maps, sevice-policies consistent across the switches within the network even down to the port configuration?  I am looking over some configs from our vendor managed network and to the QOS challenged there is not what I can see or call consistency across the switches. If there should be some sort of consistent QOS across the switches what command do run to verify its existence?

[Reza Sharifi]

Unfortunately consistency is not always the case when it comes to Cisco hardware and software.  You may find similarity between platforms, but not all command are the same for every platform.  You would need to use the config guide to configure qos based on the platform and the the IOS version you are using.  It is case by case.  You can usually issue "sh mls qos" to figure out if qos is enabled globally and also use "sh mls qos interface xx" for qos config info on an interface. 

here is an example from a 3750:

Switch#sh mls qos interface gigabitEthernet 1/0/1

GigabitEthernet1/0/1

trust state: not trusted

trust mode: not trusted

trust enabled flag: ena

COS override: dis

default COS: 0

DSCP Mutation Map: Default DSCP Mutation Map

Trust device: none

qos mode: port-based

Switch#              

HTH

[Joseph W. Doherty]

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Posting

As Peter has already described, different Catalyst switches often have different QoS capabilities because of their hardware.  The 3750 series and 2960 series are very similar.  I haven't worked with a 2970, so I'm unfamiliar with its QoS capabilities but suspect its also very similar.

AutoQoS does try to implement the same logical QoS policy on different platforms.  However, there's several versions of AutoQoS policies.  Which version you have depends on the version of IOS the switch is running. I think the latest version is still V4, see: http://www.cisco.com/en/US/docs/solutions/Enterprise/WAN_and_MAN/QoS_SRND_40/QoSCampus_40.html