DNAT with DDNS throw VPN

[Noori]

I have two Sites (Site A) using Fortiddns, and Site B using Daillup . There is VPN tunnel between them and it's working fine. I want to make DNAT for my server and it's behind Site B. I don't have public IP Addresd .

it's not working in this scenario? 

[AEK · Accepted solution]

If I understand well your case, DNAT should be on site-A, mapping the site-A's public IP address to the server's IP address that is located on site-B.

What is not working? Any logs? Any blocked traffic?

[Noori]

Yes. exactly but I don't have static public IP address. we use Fortiddns . and the two sites connected throw VPN. 

[AEK]

In your VIP, you just need to put 0.0.0.0 as External IP address, and it should work.

[Noori]

Yes its 0.0.0.0 . but what I notice if I want to make Ping from Site A Fortigate to the server that behind the Site B Fortigate . the Ping  Faile 

[AEK]

You need to check if firewall rules allow the traffic on both FortiGates, and your IPsec phase2 selectors on both sites include the communicating sources and destinations.

[Noori]

for source Add that camming from the internet throw the WAN interface the use DDNS . what source add should be