WCCP—Fast Timers

The Web Cache Communication Protocol (WCCP)—Fast Timers feature enables WCCP to establish redirection using a configurable message interval when a WCCP client is added to a service group or when a WCCP client fails.

The WCCP message interval capability introduced by the WCCP-Fast Timers feature defines the transmission interval that WCCP clients and WCCP routers use when sending keepalive messages and defines a scaling factor used when calculating the timeout value. The WCCP router uses the timeout value to determine if a WCCP client is no longer available and to redirect traffic as a result.

Finding Feature Information

Your software release may not support all the features documented in this module. For the latest caveats and feature information, see Bug Search Tool and the release notes for your platform and software release. To find information about the features documented in this module, and to see a list of the releases in which each feature is supported, see the feature information table at the end of this module.

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Information About WCCP—Fast Timers

WCCP—Fast Timers Overview

The WCCP—Fast Timers feature enables WCCP to establish redirection using a configurable message interval when a WCCP client is added to a service group or when a WCCP client fails. WCCP routers and WCCP clients exchange keepalive messages at a fixed interval. Prior to the introduction of the WCCP—Fast Timers feature, the WCCP message interval was fixed at 10 seconds. The WCCP—Fast Timers feature enables use of message intervals ranging from 0.5 seconds to 60 seconds and a timeout value scaling factor of 1 to 5. The default is 10 seconds. The timer interval is driven by the WCCP client which is being redirected to. The WCCP clients must support variable message interval timers in order for the WCCP—Fast Timers feature to function correctly.

The WCCP message interval capability introduced by the WCCP—Fast Timers feature defines the transmission interval that WCCP clients and WCCP routers use when sending keepalive messages and defines a scaling factor used when calculating the timeout value. The WCCP router uses the timeout value to determine if a WCCP client is no longer available and to redirect traffic as a result. The WCCP router enforces a single message interval per service group. WCCP clients with incompatible message intervals are prevented from joining a service group. If a default message interval that is smaller than the default 10 seconds is used, CPU usage will increase.

You can use the show ip wccp service service-number detail command to display information about the message interval.

How to Configure WCCP—Fast Timers

Displaying WCCP—Fast Timers Information

SUMMARY STEPS

  1. enable
  2. show ip wccp [ [ service-number] [ detail ] ]

DETAILED STEPS

  Command or Action Purpose
Step 1

enable

Example:


Device> enable

Enables privileged EXEC mode.

  • Enter your password if prompted.

Step 2

show ip wccp [ [ service-number] [ detail ] ]

Example:


Device# show ip wccp 24 detail
Displays WCCP client information that includes the message interval information.

  • The message interval is the fixed time interval between successive keepalive messages sent from a WCCP client to a WCCP router. The default time interval is 10 seconds. If the default time interval is configured, the "Message Interval" field is not displayed.

Note 

You configure the time interval on the WCCP client device. Details of the client configuration are specific to each type of client, so you should consult the documentation of your WCCP client device. Client devices may choose not support the full range of settings that are supported by the router.

Configuration Examples for WCCP—Fast Timers

Example: Displaying WCCP-Fast Timers Information

The following example displays WCCP client information that includes the message interval information: 


Device# show ip wccp 91 detail

WCCP Client information:
 WCCP Client ID: 10.1.1.14
 Protocol Version: 2.0
 State: Usable
 Redirection: GRE
 Packet Return: GRE
 Assignment: MASK
 
 
Message Interval: 2.500 seconds (2.354 since last message)
 Client timeout: 15 seconds
 Assignment timeout: 25 seconds
 Packets Redirected: 0
 Connect Time: 00:01:56
 Bypassed Packets
 Process: 0
 CEF: 0

Additional References For IP Services

Related Documents

Related Topic

Document Title

Cisco IOS commands

Cisco IOS Master Commands List, All Releases

IP application services commands

Cisco IOS IP Application Services Command Reference

Standards and RFCs

Standard

Title

RFC 1256

ICMP Router Discovery Messages

Technical Assistance

Description

Link

The Cisco Support and Documentation website provides online resources to download documentation, software, and tools. Use these resources to install and configure the software and to troubleshoot and resolve technical issues with Cisco products and technologies. Access to most tools on the Cisco Support and Documentation website requires a Cisco.com user ID and password.

http://www.cisco.com/cisco/web/support/index.html

Feature Information for WCCP—Fast Timers

The following table provides release information about the feature or features described in this module. This table lists only the software release that introduced support for a given feature in a given software release train. Unless noted otherwise, subsequent releases of that software release train also support that feature.

Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to www.cisco.com/go/cfn. An account on Cisco.com is not required.
Table 1. Feature Information for WCCP—Fast Timers

Feature Name

Releases

Feature Information

WCCP—Fast Timers

15.1(1)SG

15.2(3)T

Cisco IOS XE Release 3.3SG

The Web Cache Communication Protocol (WCCP)—Fast Timers feature enables WCCP to establish redirection using a configurable message interval when a WCCP client is added to a service group or when a WCCP client fails.

The WCCP message interval capability introduced by the WCCP-Fast Timers feature defines the transmission interval that WCCP clients and WCCP routers use when sending keepalive messages and defines a scaling factor used when calculating the timeout value. The WCCP router uses the timeout value to determine if a WCCP client is no longer available and to redirect traffic as a result.

The following command were modified: show ip wccp .