Hi @kvsivasakthi
In FortiGate, VIP (Virtual IP) lookup is performed before policy lookup.
Here's how FortiGate processes the traffic in your scenario:
1. FortiGate will first check if there is a VIP configured for the destination IP address in the incoming traffic.
In your case, the VIP vip_123.1.1.10 is configured with the external IP 123.1.1.10.
2. If a VIP is found, FortiGate will use the mapped IP (10.1.1.100) for policy lookup. However, since your policy uses the actual external IP (123.1.1.10) instead of the VIP object, the policy will not match the traffic.
3. As a result, the traffic will not be processed as expected because the policy does not reference the VIP object.
The traffic will be dropped if no matching policy is found.
4. To ensure the traffic is processed correctly, you should use the VIP object (vip_123.1.1.10) in the destination field of your firewall policy instead of the actual external IP.
This allows FortiGate to correctly map the external IP to the internal IP and apply the appropriate policy.
Thanks, Erlin