Match Precedence - Cisco NCS 540 Series Routers Command Reference Manual

QoS Classification Commands

match precedence

To identify IP precedence values as match criteria, use the match precedence command in class map
configuration mode. To remove precedence values from a class map, use the no form of this command.
match [not] precedence [{ipv4|ipv6}] precedence-value [precedence-value1 ... precedence-value7]
no match [not] precedence [{ipv4|ipv6}] precedence-value [precedence-value1 ...
precedence-value7]
Syntax Description
not
ipv4
ipv6
precedence-value
Matching on both IP Version 4 (IPv4) and IPv6 packets is the default.
Command Default
Class map configuration
Command Modes
Command History
Release
Release 6.0
The match precedence command is supported only in the ingress direction. The minimum value is 0 and
Usage Guidelines
maximum value is 7. The maximum allowed entries: 8.
The match precedence command specifies a precedence value that is used as the match criteria against which
packets are checked to determine if they belong to the class specified by the class map.
To use the match precedence command, you must first enter the class-map command to specify the name
of the class whose match criteria you want to establish. If you specify more than one match precedence
command in a class map, the new values are added to the existing statement.
The match precedence command examines the higher-order three bits in the type of service (ToS) byte of
the IP header. Up to eight precedence values can be matched in one match statement. For example, match
precedence ipv4 0 1 2 3 4 5 6 7 returns matches for IP precedence values of 0, 1, 2, 3, 4, 5, 6, and 7. Only
one of the eight values is needed to yield a match (OR operation).
The precedence values are used as a matching criterion only. The value has no mathematical significance.
For instance, the precedence value 2 is not greater than 1. The value simply indicates that a packet marked
with the precedence value of 2 is different than a packet marked with the precedence value of 1. The treatment
of these different packets is defined by the user through the setting of QoS policies in policy map class
configuration mode.
This table lists the IP precedence value number and associated name in descending order of importance.
(Optional) Negates the specified match result.
(Optional) Specifies the IPv4 precedence value.
(Optional) Specifies the IPv6 precedence value.
An IP precedence value identifier that specifies the exact value. Reserved keywords can
be specified instead of numeric values.
page 22 describes the reserved keywords.
Up to eight precedence values can be matched in one match statement.
Modular QoS Command Reference for Cisco NCS 5500 Series and Cisco NCS 540 Series Routers
Table 3: IP Precedence Values and Names, on
Modification
This command was introduced.

match precedence

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