Sophos XG behind Fortigate firewall

Far easier is to actually get Fortiextender and replace both XG and Sophos red. On FortiExtender you can do QoS and filtering if required. Without LTE modem, should be low cost.

However, if you are willing to use this setup, then it depends on where you do NATing. It there is no NAT, then it is only routing where you need to add manually routes on XG as well as on Fortigate. However, if you add routes that all Ok but you still need to add policies on both firewalls for traffic to flow. 

Can you please guide me rules and routing that I must setup to achieve what you suggest.?

on FG side
- add site B subnet as object
- add static route to that subnet as next gw port 8 on XG

- add policy to allow trafic in both direction

on XG side do same thing in opposite direction

I added the routes, I can ping from site B to Sophos firewall but not to  Fortigate firewall la, any idea why?

one silly question, if I do IPsec on the 3 firewalls, like FortiGate connected to XG and XG connected to the red device, will I be able to reach the Fortigate from site B?

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