If an IPS diagnostic command outcome shows a decrease in CPU usage after using option 5, what does this imply?

The correct interpretation of seeing a decrease in CPU usage after using option 5 in an IPS diagnostic command indicates that resources have been reallocated to other processes. This is generally a positive outcome, as the IPS engine is designed to inspect and analyze traffic for potential threats, and its operation can require significant CPU resources.

When you notice a decrease in CPU usage, it suggests that the IPS may have either paused its inspection or has delegated some of the intensive tasks to other resources or processes within the FortiGate device. This reallocation occurs when the traffic or the workload handled by the IPS reduces, allowing for a more efficient use of CPU resources. A lower CPU utilization doesn't necessarily indicate that the IPS is not functioning or processing traffic, but rather that it has optimized its performance by potentially scaling down the load on the CPU.

The possibility of the IPS engine inspecting a high volume of traffic would typically manifest as higher CPU usage, so that scenario does not align with the observed decrease. Likewise, if the FortiGate were not processing any IPS traffic or if the engine had failed completely, you would expect a consistently low CPU usage or erratic readings, rather than the specific decrease showing efficiency.