RCSP Study Guide - Connection Forwarding
In WCCP deployments, Connection Forwarding can also be used to prevent outages whenever the cluster and the redirection table changes.
Default behavior of Connection Forwarding is that when a neighbor is lost, the Steelhead appliance that lost the neighbor also will pass through the connection since it is assuming asymmetric routing of traffic. In WCCP deployments this is not the case and this behavior has to be avoided.
in-path neighbor allow-failure
overrides the default behavior and allows the Steelhead appliances to continue optimizing. Understanding the implication of applying this command prior to configuring it in a production environment is recommended.