In virtual inline mode, unlike WCCP mode, the appliance provides no virtual inline-specific monitoring. To troubleshoot a virtual inline deployment, log into the appliance and use the Dashboard page to verify that traffic is flowing into and out of the appliance. Traffic forwarding failures are typically caused by errors in router configuration.
If the Monitoring: Usage or Monitoring: Connections pages show that traffic is being forwarded but no acceleration is taking place (assuming that an appliance is already installed on the other end of the WAN link), check to make sure that both incoming WAN traffic and outgoing WAN traffic are being forwarded to the appliance. If only one direction is forwarded, acceleration cannot take place.
To test health-checking, power down the appliance. The router should stop forwarding traffic after the health-checking algorithm times out.