Cisco N5010P-N2K-BE, Software Configuration Manual

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S e n d f e e d b a c k t o n x 5 0 0 0 - d o c f e e d b a c k @ c i s c o . c o m
31-9
Cisco Nexus 5000 Series Switch CLI Software Configuration Guide
OL-16597-01
Chapter 31 Configuring QoS
Configuring System Classes
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Verifying Jumbo MTU, page 31-12
Configuring Class Maps
The class-map command creates a named object that represents a class of traffic. In the class map, you
specify a set of match criteria for classifying the packets. For system classes, the only match criteria
supported is
match cos .
If a system class is configured with 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 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. PFC Pause will be applied to traffic that matches the new value.
To configure a class map for a system class, perform this task:
Configuring Policy Maps
The policy-map command is used to create a named object representing a set of policies that are to be
applied to a set of traffic classes.
The switch provides two default system classes: a no-drop class for lossless service and a drop class for
best-effort service. You can define up to four additional system classes for Ethernet traffic.
You need to create a policy map to specify the policies for any user-defined class. In the policy-map, you
can configure the QoS parameters for each class. You can use the same policy map to modify the
configuration of the default classes.
Note
Before creating the policy map, define a class map for each new system class.
Command Purpose
Step 1
switch# configure terminal
Enters configuration mode.
Step 2
switch(config)# class-map 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)# 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.