Configuring Fortigate firewall for RDP connection to Windows Server with specified IP

[Userlam]

We are using the Fortigate product Fortigate 61F, which has a Windows RDP connection. When not specifying an IP, it can be accessed normally. However, when specifying an IP, the connection cannot be established to the server. We have checked that this issue does not occur on other brands of firewalls. We would like to inquire if Forti products have a different approach to this issue and how to configure the Fortigate firewall to enable RDP connection to Windows Server using a specified IP.

[Userlam]

[srajeswaran]

When it is not working, do you see a traffic deny log on Fortigate traffic logs?

[abarushka]

Hello,

I suspect that NAT is performed by FortiGate. Therefore, NATed IP address is blocked by Windows.

[Userlam]

@abarushka  Hello, Can I convert this NATed IP to a regular IP in the firewall setting?

Also, is this NATed IP address same as the FortiGate 61F? 

Thanks

[abarushka]

Hello,

By default NAT is configured under firewall policy and outbound interface IP of firewall will be used for NATed traffic. 

[ebilcari · Accepted solution]

You can try to disable NAT checkbox on the firewall policy that allow traffic to the VIP. In this way the source/remote IP that is trying to reach the RDP will not be replaced by FGT IP.