Refer to the exhibits.

The reason for the ping failures is due to the quick mode selectors restricting the subnet. Quick mode selectors define the IP ranges and protocols that are allowed through the VPN tunnel, and if they are not configured correctly, traffic to certain subnets can be blocked.

Quick Mode Selectors:

Quick mode selectors specify the source and destination subnets that are allowed to communicate through the VPN tunnel.

If the selectors do not include the subnet of the webserver (192.168.10.0/24), then the traffic will be restricted, and the ping will fail.

Diagnostic Output:

The diagnostic output shows the VPN configuration details, but it is important to check the quick mode selectors to ensure that the necessary subnets are included.

If the quick mode selectors are too restrictive, they will prevent traffic to and from the specified subnets.

Configuration Check:

Verify the quick mode selectors on both the FortiSASE and FortiGate hub to ensure they match and include the subnet of the webserver.

Adjust the selectors to allow the necessary subnets for successful communication.

References:

FortiOS 7.2 Administration Guide: Provides detailed information on configuring VPN tunnels and quick mode selectors.

FortiSASE 23.2 Documentation: Explains how to set up and manage VPN tunnels, including the configuration of quick mode selectors.