Cisco Systems OL-8550-09 Classifying Traffic by Using Class Maps

35-51
Catalyst 3750 SwitchSoftware Configuration Guide
OL-8550-09
Chapter35 Configuring QoS
Configuring Standard QoS
Classifying Traffic by Using Class Maps
You use the class-map global configuration command to name and to isolate a specific traffic flow (or
class) from all other traffic. The class map defines the criteria to use to match against a specific traffic
flow to further classify it. Match statements can include criteria such as an ACL, IP precedence values,
or DSCP values. The match criterion is defined with one match statement entered within the class-map
configuration mode.
Note You can also create class-maps during policy map creation by using the class policy-map configuration
command. For more information, see the “Classifying, Policing, and Marking Traffic on Physical Ports
by Using Policy Maps” section on page35-53 and the “Classifying, Policing, and Marking Traffic on
SVIs by Using Hierarchical Policy Maps” section on page35-57.
Beginning in privileged EXEC mode, follow these steps to create a class map and to define the match
criterion to classify traffic:
Command Purpose
Step1 configure terminal Enter global configuration mode.
Step2 access-list access-list-number {deny |
permit} source [source-wildcard]
or
access-list access-list-number {deny |
permit} protocol source [source-wildcard]
destination [destination-wildcard]
or
mac access-list extended name
{permit | deny} {host src-MAC-addr mask
| any | host dst-MAC-addr | dst-MAC-addr
mask} [type mask]
Create an IP standard or extended ACL for IP traffic or a Layer2 MAC
ACL for non-IP traffic, repeating the command as many times as
necessary.
For more information, see the “Classifying Traffic by Using ACLs”
section on page 35-48.
Note When creating an access list, remember that, by default, the
end of the access list contains an implicit deny statement for
everything if it did not find a match before reaching the end.
Step3 class-map [match-all | match-any]
class-map-name
Create a class map, and enter class-map configuration mode.
By default, no class maps are defined.
•(Optional) Use the match-all keyword to perform a logical-AND
of all matching statements under this class map. All match criteria
in the class map must be matched.
•(Optional) Use the match-any keyword to perform a logical-OR
of all matching statements under this class map. One or more
match criteria must be matched.
•For class-map-name, specify the name of the class map.
If neither the match-all or match-any keyword is specified, the default
is match-all.
Note Because only one match command per class map is supported,
the match-all and match-any keywords function the same.