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static natting

i have 100E with polcibased routing enabled for servers network 

i configured static natting for a server using virtual IP,

the server is going out with the mapped external IP i provided but when i try to establish any kind of connection to that server using the external IP it doesnt work, like rdp or ssh etc 




The PBR seems to be configured for Internal to external traffic. This does not assure that when the traffic is initiated from outside, the FortiGate will allow the traffic as RPF ( Reverse Path Forwarding) check will be done initially by the FortiGate and if FortiGate does not find the route of the source associated with the incoming interface, then FortiGate will drop the packets from that source


To see if the FortiGate is blocking the connection due to RPF check or not, you can run the below commands:


diag debug flow filter addr <source IP>

diag debug flow show iprope enable

diag debug flow show function-name enable

diag debug console timestamp enable

diag debug flow trace start 1000

diag debug enable


Then initiate the traffic and see if you see any rpf check failed messages or not. Also, it will show how FortiGate is processing the packets.


Also, you can take the packet captures in the first place to see if the traffic is arriving on the FortiGate or not


diag sniffer packet any "host <source ip>" 4 0 l


If RPF check is failing then you can disable RPF check on the incoming interface

config system interface
edit <interface>
set src-check disable


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