Warning message upon port exhaustion (7.6.0)

FortiWeb allocates a different port number (ranging from 1024 to 65535) for each connection with the back-end server to distinguish these connections. When the port numbers are nearly exhausted, CPU usage will be high. It is suggested to create a new network interface for the back-end server connections when facing port exhaustion.

It's important to stay informed about the port exhaustion situation so that you can take timely action to avoid CPU high usage. An efficient way to achieve this is by configuring FortiWeb to generate Port Exhaustion logs based on port usage levels:

config system network-option

set ip-local-port-warning-threshold {high | normal | low | disable}

end

• High: The ports are almost fully utilized.

• Normal: There are a few available ports, and the system is struggling to allocate ports to all current connections. It is highly likely that the ports will soon be exhausted.

• Low: There are some available ports, and the system is functioning adequately. However, you should be prepared for the possibility that ports might be exhausted during a traffic spike.

• disable: Stop generating port exhaustion logs.

Here is an example of the port exhaustion log.

To troubleshoot port exhaustion issue, refer to "Check if high CPU usage is caused by port exhaustion" in Checking CPU information&Issues.