Virtual IP port forwarding with WAN Link Load Balancing

[elmasrydev]

Hello 

Short Story: How to get Virtual IP port forwarding work with WLLB ?

Long Story:

I have Fortigate 100E with OS v5.4 working as main gateway for my network and acting as WAN Link Load Balancing for 2 WAN fiber connections on port WAN1, WAN2.

I'm using DDNS service and routed 2 DDNS updater clients traffic through WAN1 and WAN2 respectively using WLLB rules.

When i ping the both DDNS domains there is reply from my both public IP addresses and my 2 fiber modems configured Fortigate unit as DMZ and until this point everything works great and i can access Fortigate unit from internet.

My issue is when i would like to configure the Virtual IP port forwarding ex:(fortigate_ip:port1 > lan_ip:port2) it doesn't work ! however if i did the same but without using WLLB and with using the 2 WAN connections separately it work fine !

I did everything about the IPv4 policies. i allowed traffic from (lan_int,lan_add) to (wllb_int,add_any) and also vise versa.

The only thing i noticed is the settings for Virtual IP in case of using the WLLB that the WLLB interface is not showing in the interface list which is logic since traffic could arrive from 2 different WAN links but if i did the same without using WLLB the port forwarding works !

I tried using IPSEC vpn with WLLB and it works.

Anyone have a clue what wrongs or what should i do to get Virtual IP port forwarding work with WLLB?

Best Regards.