Bounce traffic is occurring on an interface

This threshold is designed to identify improperly configured routes on your network devices. Bounce traffic is defined as traffic that arrives and leaves on the same interface in a flow-enabled device. For example, RouterA has been configured to send traffic for 192.168.4.x out Interface 2 which connects to Interface 5 on RouterB. But, instead of forwarding that traffic on to the proper location, RouterB has been incorrectly configured to send traffic for 192.168.4.x out Interface 5 back to RouterA. When RouterB sends traffic destined for 192.168.4.32 to RouterA, it will bounce back to RouterB, since RouterA cannot directly pass the traffic to the intended destination.

To isolate the router which has been improperly configured, follow these steps:

  1. Open the Alert Center Item Details dialog for the bounce traffic threshold item.
    • From any dashboard view or report in the web interface, select GO. The GO menu appears.
    • If the WhatsUp section is not visible, click WhatsUp. The WhatsUp section of the GO menu appears.
    • Click Alert Center. The Alert Center Home page appears.
    • In any of the workspace reports that display out of threshold items, click a device. The Alert Center Item Details dialog appears.
  2. Note the time the threshold was triggered, and the Aspect information.
  3. Open the Interface Details report.
    • From any workspace view or report in the web interface, select GO. The GO menu appears.
    • Click the Flow Monitor icon. The Flow Monitor Home page appears.
    • From the list of Flow sources, select an interface. The Flow Monitor Interface Details report appears.
  4. If the following workspace reports are not already part of the view's layout, add them via the Configure Flow Interface Report dialog.
    • Top Protocols
    • Top Applications
    • Top Senders
    • Top Receivers
    • Top Conversations
  5. You can add these reports to an existing workspace view, or you may want to create a new view for the purposes of isolating the improperly configured device. For more information, see Managing report views.
  6. Using the Interface list, select the interface that recorded the bounce traffic. Refer to the Aspect information contained in the Item Details dialog.
  7. Set the Traffic direction to Bounce.
  8. Set the Date range to a time period that includes the time when the Health threshold was triggered. You can use one of the pre-defined date ranges, or select Custom and specify the time period more specifically. Refer to the information in the Item Details dialog.
  9. The Top Conversations workspace report contains summary information about the traffic that is bouncing and indicates the IP address or hostname sending the traffic to the interface listed in the threshold, as well as the intended destination for the traffic. In most cases, the source of the traffic has been improperly configured to route traffic to the wrong device and this generates bounce traffic. However, the improper configuration can also exist within the displayed device. You should examine your network topology to determine the correct route for the traffic and update the improperly configured device. You can use the other workspace reports in the view to obtain more detailed information about the traffic that is being directed to the wrong location, such as the types of protocols, number of packets, and application type.