The debug flow output shows the result of a diagnose command that captures the traffic flow between the source and destination IP addresses1. The debug flow output reveals the following information about the traffic flow1:
The protocol is 1, which means that the traffic uses ICMP protocol2. ICMP is a protocol that is used to send error messages and test connectivity between devices2.
The session state is 0, which means that a new traffic session was created3. A session is a data structure that stores information about a connection between two devices3.
The policy ID is 1, which means that the traffic matched the firewall policy with ID 14. A firewall policy is a rule that defines how FortiGate processes traffic based on the source, destination, service, and action parameters4.
The action is 0, which means that the traffic was allowed by the firewall policy. An action is a parameter that specifies what FortiGate does with the traffic that matches a firewall policy.
Therefore, two conclusions that can be made from the debug flow output are:
The debug flow is for ICMP traffic.
A new traffic session was created.