How to configure Fortiweb on one-arm reverse proxy mode?

on fortiweb:

connect your fortiweb to your router or fortigate via layer3 connection and set specific ip/subnet for example 192.168.10.0/24

set one of ip in this range to fortigate or router , for example port2 192.168.10.1/24

set another ip from this rane to your fortiweb , for example port1 192.168.10.2/24

then use another ip of this range to configure your VIRTUAL SERVER on your fortiweb :192.168.10.3-192.168.10.4

make sure that fortiweb sees back-end server and exist route on your fortiweb

you can use execute ping <Physical_Server_IP_address> to understand it.

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on your fortigate and router

route HTTP and HTTPS traffic to fortiweb

fortiweb will change source ip of packets , and all of http/s traffic will be send to back-end web server by fortiweb ip address

then use x-forwarded-for to add specific header . x-forwarded-for will send client ip address to back-end server