Cisco IE 4000, Руководство по настройке программного обеспечения

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Configuring QoS
Understanding QoS
You can match more than one criterion for classification. You can also create a class map that requires that all matching
criteria in the class map be in the packet header by using the
class map match-all class-map name global configuration
command to enter class map configuration mode.
Note: You can configure only one match entry in a match-all class map.
You can use the class map match-any class-map name global configuration command to define a classification with
any of the listed criteria.
Note: If you do not enter match-all or match-any , the default is to match all. A match-all class map cannot have more
than one classification criterion (match statement). A class map with no match condition has a default of match all .
The match Command
To configure the type of content used to classify packets, you use the match class-map configuration command to
specify the classification criteria. If a packet matches the configured criteria, it belongs to a specific class and is
forwarded according to the specified policy. For example, you can use the
match class-map command with CoS, IP
DSCP, and IP precedence values. These values are referred to as markings on a packet. You can also match an access
group, a QoS group, or a VLAN ID or ID range for per-port, per-VLAN QoS.

For an input policy map, you cannot configure an IP classification ( match ip dscp , match ip precedence , match
access-group for an IP ACL) and a non-IP classification ( match cos or match access-group for a MAC ACL) in the
same policy map or class map.

When an input policy map with only Layer 2 classification is attached to a routed port or a switch port containing a
routed switch virtual interface (SVI), the service policy acts only on switching eligible traffic and not on routing eligible
traffic.

On an 802.1Q tunnel port, you can use only an input policy map with Layer 2 classification based on MAC ACLs to
classify traffic. Input policy maps with Layer 3 classification, match Layer 2 CoS classification, or per-port, per-VLAN
policies are not supported on tunnel ports.

In an output policy map, no two class maps can have the same classification criteria, that is, the same match
qualifiers and values.
This example shows how to create a class map example to define a class that matches any of the listed criteria. In this
example, if a packet is received with the DSCP equal to 32 or a 40, the packet is identified (classified) by the class map.
Switch(config)# class-map match-any example
Switch(config-cmap)# match ip dscp 32
Switch(config-cmap)# match ip dscp 40
Switch(config-cmap)# exit
Classification Based on Layer 2 CoS
You can use the match command to classify Layer 2 traffic based on the CoS value, which ranges from 0 to 7.
Note: A match cos command is supported only on Layer 2 802.1Q trunk ports.
This example shows how to create a class map to match a CoS value of 5:
Switch(config)#
class-map premium
Switch(config-cmap)# match cos 5
Switch(config-cmap)# exit
Classification Based on IP Precedence
You can classify IPv4 traffic based on the packet IP precedence values, which range from 0 to 7.