Configuring Ip Precedence Marking - Cisco Nexus 9000 Series Configuration Manual

Configuring IP Precedence Marking

Command or Action
switch# configure terminal
switch(config)#
Step 2 policy-map [type qos] [match-first] policy-map-name
Example:
switch(config)# policy-map policy1
switch(config-pmap-qos)#
Step 3 class [type qos] {class-name | class-default} [insert-before
before-class-name]
Example:
switch(config-pmap-qos)# class class1
switch(config-pmap-c-qos)#
Step 4 set dscp dscp-value
Example:
switch(config-pmap-c-qos)# set
dscp af31
Example
This example shows how to display the policy-map configuration:
switch# show policy-map policy1
Configuring IP Precedence Marking
You can set the value of the IP precedence field in bits 0–2 of the IPv4 type of service (ToS) field of the IP
header.
Note The device rewrites the last 3 bits of the ToS field to 0 for packets that match this class.
Table 32: Precedence Values
Value
0-7
critical
flash
flash-override
immediate
Cisco Nexus 9000 Series NX-OS Quality of Service Configuration Guide, Release 7.x
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Purpose
Creates or accesses the policy map named policy-map-name
and then enters policy-map mode. The policy-map name
can contain alphabetic, hyphen, or underscore characters,
is case sensitive, and can be up to 40 characters.
Creates a reference to class-name and enters policy-map
class configuration mode. The class is added to the end of
the policy map unless insert-before is used to specify the
class to insert before. Use the class-default keyword to
select all traffic that is not currently matched by classes in
the policy map.
Sets the DSCP value to dscp-value. Standard values are
shown in the previous Standard DSCP Values table.
When the QoS policy is applied on the VLAN configuration
level, the DSCP value derives the CoS value for bridged
and routed traffic from the 3 most significant DSCP bits.
List of Precedence Values
IP precedence value
Critical precedence (5)
Flash precedence (3)
Flash override precedence (4)
Immediate precedence (2)
Configuring Marking