Chapter 4 Configuring Class Maps and Policy Maps
Class Map and Policy Map Overview
4-6
Cisco 4700 Series Application Control Engine Appliance Administration Guide
OL-11157-01
When multiple match criteria exist in the traffic class, you can identify evaluation
instructions by using the
match-any
or
match-all
keywords. If you specify
match-any
as the evaluation instruction, the traffic being evaluated must match
one of the specified criteria, which are typically
match
commands of the same
type. If you specify
match-all
as the evaluation instruction, the traffic being
evaluated must match all of the specified criteria, which are typically
match
commands of different types.
The specification of complex match criteria by using the
match-all
or
match-any
keywords for Layer 7 HTTP load-balancing applications is useful as a means to
provide the nesting of one class map within a second class map. For example, you
can specify a match criteria for load balancing where the URL is either /foo or /bar
and the header “host” equals “thishost.”
host1/Admin(config)#
class-map type http loadbalance match-any
URLCHK_SLB_L7_CLASS
host1/Admin(config-cmap-http-lb)#
match http url /foo
host1/Admin(config-cmap-http-lb)#
match http url /bar
host1/Admin(config-cmap-http-lb)#
exit
host1/Admin(config)#
class-map type http loadbalance match-all
URLHDR_SLB_L7_CLASS
host1/Admin(config-cmap-http-lb)#
match http header host header-value
thishost
host1/Admin(config-cmap-http-lb)#
match class-map URLCHK_SLB_L7_CLASS
host1/Admin(config-cmap-http-lb)#
exit
The ACE allows you to configure two Layer 7 HTTP load-balancing class maps
in a nested traffic class configuration to create a single traffic class. You can
perform Layer 7 class map nesting to achieve complex logical expressions. The
ACE restricts the nesting of class maps to two levels to prevent you from
including one nested class map under a different class map.
Policy Maps
The
policy-map
command creates the traffic policy. The purpose of a traffic
policy is to implement specific ACE functions associated with a traffic class. A
traffic policy contains the following components:
•
Policy map name
•
Previously created traffic class map or, optionally, the class-default class map
•
One or more of the individual Layer 3 and Layer 4 or Layer 7 policies that
specify the actions (functions) to be performed by the ACE