You should have considered the routing protocol before getting a new FW. Only way to put router/FW that doesn't support EIGRP like FortiGate in to Cisco network with EIGRP is finding a common protocol like OSPF or BGP that the FGT supports then redistribute routes between EIGRP and OSPF/BGP at the Cisco VSS switch like below.
I would to thank you for your responses, but the problem here that i have many routes configured in my switchs and i cannot change the routing protocol because it will be very critical. So i'm asking here if there are some features in Fortigate to solve this case.
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