FortiGate Next Generation Firewall utilizes purpose-built security processors and threat intelligence security services from FortiGuard labs to deliver top-rated protection and high performance, including encrypted traffic.
This artilce describes how to configure Fortigate-VM load balancer using dynamic address objects.

FortiOS supports using dynamic firewall addresses in real servers under a virtual server load balancing configuration.
It is not necessary to manually change each server's IP address whenever a scale in/out action occurs, as FortiOS dynamically updates the IP addresses following each scale in/out action.
Consider a scenario where the FortiGate-VM is deployed on AWS and load balancing for three servers.

The Fabric connector configured in FortiOS dynamically loads the server IP addresses.
If a scale in action occurs, the load balancer dynamically updates to load balance to the two remaining servers.

The following instructions assume the following:
1) An AWS Fabric connector is configured and up.
2) An AWS dynamic firewall address with a filter is configured.

To configure a dynamic address object in a real server under virtual server load balance:

CLI commands introduced in FortiOS 6.4 are shown below.
# config firewall vip
    edit "0"
        set id 0
        set uuid 0949dfbe-7512-51ea-4671-d3a706b09657
        set comment ''
        set type server-load-balance
        set extip
        set extintf "port1"
        set arp-reply enable
        set server-type http
        set nat-source-vip disable
        set gratuitous-arp-interval 0
        set http-ip-header disable
        set color 0
        set ldb-method static
        set http-redirect disable
        set persistence none
        set extport 80
# config realservers
    edit 1
        set type address
        set address "aws addresses"  <----- This is a custom address object with type 'Dynamic'.
        set port 8080
        set status active
        set holddown-interval 300
        set healthcheck vip
        set max-connections 0
            unset client-ip
        set http-multiplex disable
        set max-embryonic-connections 1000
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