IP Application Services Configuration Guide, Cisco IOS Release 15M&T
WCCP—Fast Timers
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WCCP—Fast Timers

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.

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.

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 ActionPurpose
    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

    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.