Overload PBA port-reuse limitation for traffic between a single source and destination IP address

Because of an NP7 hardware limitation, port-reuse does not work as expected when processing multiple sessions between a single client IP address and a single server IP address when using an overload with port-block-allocation CGN IP pool. The hardware limitation prevents the NP7 processor from establishing all of the required sessions and some sessions will time out sooner than expected.

It is very unlikely for this condition to occur. A client is most likely to always be connecting to many different servers. If they are connecting multiple times to the same server, they are most likely using multiple server ports.

Here are three possible ways to resolve the issue:

• Use a non-overload PBA CGN IP pool.

• Use an overload PBA CGN IP pool but reduce the ippool-overload-high threshold:

  config system npu

  set ippool-overload-high <threshold>

  end

  The default <threshold> is 200, for example, you could reduce the threshold to 100.

• Change the network to increase the number of client or server IP addresses.