Wccpv1 Configuration - Cisco ASR 1000 Series Configuration Manual

Configuring WCCP

WCCPv1 Configuration

With WCCPv1, only a single router services a cluster. In this scenario, this router is the device that performs
all the IP packet redirection. The figure below illustrates the WCCPv1 configuration.
Figure 3: WCCPv1 Configuration
Content is not duplicated on the content engines. The benefit of using multiple content engines is that you
can scale a caching solution by clustering multiple physical content engines to appear as one logical cache.
The following sequence of events details how WCCPv1 configuration works:
1 Each content engine is configured by the system administrator with the IP address of the control router.
Up to 32 content engines can connect to a single control router.
2 The content engines send their IP addresses to the control router using WCCP, indicating their presence.
Routers and content engines communicate to each other via a control channel; this channel is based on
UDP port 2048.
3 This information is used by the control router to create a cluster view (a list of caches in the cluster). This
view is sent to each content engine in the cluster, essentially making all the content engines aware of each
other. A stable view is established after the membership of the cluster remains the same for a certain
amount of time.
4 When a stable view has been established, one content engine is elected as the lead content engine. (The
lead is defined as the content engine seen by all the content engines in the cluster with the lowest IP
address). This lead content engine uses WCCP to indicate to the control router how IP packet redirection
should be performed. Specifically, the lead content engine designates how redirected traffic should be
distributed across the content engines in the cluster.
IP Application Services Configuration Guide, Cisco IOS XE Release 3S (Cisco ASR 1000)
WCCPv1 Configuration
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