Cisco Catalyst 4500 Series Command Reference Manual page 397

Chapter 2 Cisco IOS Commands for the Catalyst 4500 Series Switches
Command History Release
12.2(31)SG
15.0(2)SG/3.2(0)SG Supported extended to Supervisor Engine 6-E, Supervisor Engine 6L-E,
15.0(2)SG1
IOS XE 3.3.0 SG
(15.1(1)SG)
Usage Guidelines This command instructs a router to enable or disable the support for the specified service number or the
web-cache service name. A service number can be from 0 to 254. Once the service number or name is
enabled, the router can participate in the establishment of a service group.
When the no ip wccp command is entered, the router terminates participation in the service group,
deallocates space if none of the interfaces still has the service configured, and terminates the WCCP task
if no other services are configured.
The keywords following the web-cache keyword and the service-number argument are optional and may
be specified in any order, but only may be specified once. The following sections outline the specific
usage of each of the optional forms of this command.
ip wccp
A WCCP group address can be configured to set up a multicast address that cooperating routers and web
caches can use to exchange WCCP protocol messages. If such an address is used, IP multicast routing
must be enabled so that the messages that use the configured group (multicast) addresses are received
correctly.
This option instructs the router to use the specified multicast IP address to coalesce the "I See You"
responses for the "Here I Am" messages that it has received on this group address. The response is sent
to the group address as well. The default is for no group address to be configured, in which case all "Here
I Am" messages are responded to with a unicast reply.
ip wccp
This option instructs the router to use an access list to control the traffic that is redirected to the web
caches of the service group specified by the service name given. The access-list argument specifies either
the number or the name of a standard or extended access list. The access list itself specifies which traffic
is permitted to be redirected. The default is for no redirect list to be configured (all traffic is redirected).
WCCP requires that the following protocol and ports not be filtered by any access lists:
•
ip wccp
This option instructs the router to use an access list to control the cache engines that are allowed to
participate in the specified service group. The access-list argument specifies either the number of a
standard or extended access list or the name of any type of named access list. The access list itself
specifies which cache engines are permitted to participate in the service group. The default is for no
group list to be configured, in which case all cache engines may participate in the service group.
OL-25342 -01
Modification
Support introduced on the Catalyst 4500 series switch.
Catalyst 4900M, and Catalyst 4948E.
Support for redirect-list keyword.
Supported extended to Supervisor Engine 7-E and Supervisor Engine 7L-E.
{ web-cache | service-number } group-address multicast-address
{ web-cache | service-number } redirect-list access-list
User Datagram Protocol (UDP) (protocol type 17) port 2048. This port is used for control signaling.
Blocking this type of traffic will prevent WCCP from establishing a connection between the router
and cache engines.
{ web-cache | service-number } group-list access-list
Catalyst 4500 Series Switch Cisco IOS Command Reference—Release IOS XE 3.3.0SG and IOS 15.1(1)SG)
ip wccp
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