Nexus 5010 QOS Classification

[shahchirag]

Hi

I am looking to classify the traffic on nexus 5010 form particular 2232 and want to know if there is any way with nexus we can  match traffic based on source interface or any other way I can achieve this.

Thanks

[mipetrin]

Hi,

In regards to your question, you can apply a service policy directly to the FEX interface, that is, the interface where the server connects to on your Nexus 2232. Since the Nexus 2232 is just a remote line card of the Nexus 5010, all "remote" interfaces are controlled from the Nexus 5010 and appear as though they are directly attached. Only difference is that the interface number will be >100, so for example your first FEX may be registered as FEX 100. Then the first interface on this FEX will be Eth100/1/1 and this is what the Nexus 5010 will see.

You can then define your class-maps and policy-maps and then tie them together with your service-policy and apply it directly to the FEX interface.

Nexus 5000 QoS Configuration Guide

More details around the configuration can also be reviewed by looking at your specific NX-OS version configuration guide.

Hope that helps.

Regards,

Michael

[shahchirag]

Hi Michael,

Thanks for the reply.

my problem is  we have 2 server on to different 2232 replicating traffic between them. I need to reserve certain percentage of bandwidth for this replication.  I am having difficulty in classifying this traffic as sever gusy are not marking this traffic so I am not sure against which criteria I match this traffice. also I am assuming since 5k is just L2 acl with IP wouldn't work in this case.

I think what I am after is how do I mark particular CoS value based on Ingress interface

Regards,

Chirag

[Jerry Ye]

You can use IP address in the ACL to match, it will work.

Regards,

jerry

[sbhadrav@cisco.com]

This  describes how to configure quality of service (QoS) on Cisco Nexus 5000 Series switches. It contains the following sections:
https://www.cisco.com/c/en/us/td/docs/switches/datacenter/nexus5000/sw/qos/b_Cisco_Nexus_5000_Series_NX-OS_Quality_of_Service_Configuration_Guide/Cisco_Nexus_5000_Series_NX-OS_Quality_of_Service_Configuration_Guide_chapter3.html

[sbhadrav@cisco.com]

You can classify traffic based on the class of service (CoS) in the IEEE 802.1Q header. This 3-bit field is defined in IEEE 802.1p to support QoS traffic classes. CoS is encoded in the high order 3 bits of the VLAN ID Tag field and is referred to as user_priority.

If a system class is configured with a no-drop function, the match cos command serves an additional purpose. The switch sends the CoS value to the adapter so that the adapter will apply a PFC pause for this CoS value.

The FCoE system class has a default CoS value of 3. You can add a match cos configuration to the FCoE system class to set a different CoS value. A PFC pause will be applied to traffic that matches the new value.

SUMMARY STEPS
1.    switch# configure terminal

2.    switch(config)# class-map type qos class-name

3.    switch(config-cmap-qos)# match cos cos-value

4.    (Optional) switch(config-cmap-qos)# no match cos cos-value


DETAILED STEPS
     Command or Action    Purpose
Step 1    switch# configure terminal
    
Enters configuration mode.

 
Step 2    switch(config)# class-map type qos class-name
    
Creates a named object that represents a class of traffic. Class-map names can contain alphabetic, hyphen, or underscore characters, are case sensitive, and can be up to 40 characters.

 
Step 3    switch(config-cmap-qos)# match cos cos-value
    
Specifies the CoS value to match for classifying packets into this class. You can configure a CoS value in the range of 0 to 7.

Note      
When a Cisco Nexus 2148T Fabric Extender is connected and in use, data traffic should never be marked with a CoS value of 7. CoS 7 is reserved for control traffic transiting the Fabric Extender.

 
Step 4    switch(config-cmap-qos)# no match cos cos-value
     (Optional)
Removes the match from the traffic class.

 
This example shows how to classify traffic by matching packets based on a defined CoS value:

switch# configure terminal
switch(config)# class-map type qos class_cos
switch(config-cmap-qos)# match cos 4, 5-6
 
Use the show class-map command to display the CoS value class-map configuration:

switch# show class-map class_cos