Configuring Cos Classification - Cisco AP775A - Nexus Converged Network Switch 5010 Configuration Manual

Configuring System Classes
Step 4
This example shows how to classify traffic by matching packets based on existing ACLs:
switch# configure terminal
switch(config)# class-map type qos class_acl
switch(config-cmap-qos)# match access-group name acl-01
Use the show class-map command to display the ACL class-map configuration:
switch# show class-map class_acl

Configuring CoS Classification

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.
Procedure
Step 1
Step 2
Step 3
Step 4
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
OL-16597-01
Command or Action
switch(config-cmap-qos)# no match
access-group name acl-name
Command or Action
switch# configure terminal
switch(config)# class-map type
qos class-name
switch(config-cmap-qos)# match
cos cos-value
switch(config-cmap-qos)# no
match cos cos-value
Purpose
(Optional)
Removes the match from the traffic class.
Purpose
Enters configuration mode.
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.
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.
(Optional)
Removes the match from the traffic class.
Cisco Nexus 5000 Series Switch CLI Software Configuration Guide
Configuring CoS Classification
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