Fortinet Updated FCSS_SASE_AD-23 Exam Questions and Answers by gianna

The VPN tunnel between the FortiSASE spoke and the FortiGate hub is not establishing due to the configuration of mode config, which is not supported by FortiSASE spoke devices. Mode config is used to assign IP addresses to VPN clients dynamically, but this feature is not applicable to FortiSASE spokes.

Mode Config in IPsec:

The configuration snippet shows that mode config is enabled in the IPsec phase 1 settings.

Mode config is typically used for VPN clients to dynamically receive an IP address from the VPN server, but it is not suitable for site-to-site VPN configurations involving FortiSASE spokes.

Configuration Adjustment:

To establish the VPN tunnel, you need to disable mode config in the IPsec phase 1 settings.

This adjustment will allow the FortiSASE spoke to properly establish the VPN tunnel with the FortiGate hub.

Steps to Disable Mode Config:

Access the VPN configuration on the FortiSASE spoke.

Edit the IPsec phase 1 settings to disable mode config.

Ensure other settings such as pre-shared key, remote gateway, and BGP configurations are correct and consistent with the FortiGate hub.

References:

FortiOS 7.2 Administration Guide: Provides details on configuring IPsec VPNs and mode config settings.

FortiSASE 23.2 Documentation: Explains the supported configurations for FortiSASE spoke devices and VPN setups.

When configuring FortiSASE Secure Private Access (SPA) with SD-WAN integration, establishing a routing adjacency between FortiSASE and the FortiGate SD-WAN hub requires the use of the Border Gateway Protocol (BGP).

BGP (Border Gateway Protocol):

BGP is widely used for establishing routing adjacencies between different networks, particularly in SD-WAN environments.

It provides scalability and flexibility in managing dynamic routing between FortiSASE and the FortiGate SD-WAN hub.

Routing Adjacency:

BGP enables the exchange of routing information between FortiSASE and the FortiGate SD-WAN hub.

This ensures optimal routing paths and efficient traffic management across the hybrid network.

References:

FortiOS 7.2 Administration Guide: Provides information on configuring BGP for SD-WAN integration.

FortiSASE 23.2 Documentation: Details on setting up routing adjacencies using BGP for Secure Private Access with SD-WAN.