FortiGate
FortiGate Next Generation Firewall utilizes purpose-built security processors and threat intelligence security services from FortiGuard labs to deliver top-rated protection and high performance, including encrypted traffic.
pkungatti_FTNT
Article Id 192150
Description
This article explains how to configure the guest users traffic for internet access connected via the fortiAP SSID  through separate ISP link.

Solution
Situation: When there is a multiple ISP link and need to send the internet traffic for the Guest users who are connected via the Guest SSID in the fortigate through the separate ISP link interface.

Solution: Configure a Policy route to allow the guest users internet traffic to pass through the desired ISP interface as shown in the below command:
#config router policy
    edit 1
        set input-device "Guest SSID" 
         set srcaddr "Guest"--- Guest Subnet
        set dstaddr "all"
        set output-device "port"------ ISP Wan interface.
    next
end


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