Once, licensed and rebooted, the FortiGate Fabric Connector needs to be configured to enable the cluster IP and route table to failover. Most of this config will be specific to your environment and so must be modified. The authentication part by default is configured using managed identities. It can be done a service principal as well more information can be found here
config system sdn-connector
edit "AzureSDN"
set type azure
set ha-status enable
set resource-group "fortigateapha"
set subscription-id 00000000-0000-0000-0000-000000000000
config nic
edit "FortiGate-A-NIC1"
config ip
edit "ipconfig1"
set public-ip "FGTAPClusterPublicIP"
next
end
next
end
config route-table
edit "FGTDefaultAPRouteTable"
config route
edit "toDefault"
set next-hop "172.16.136.68"
next
end
next
end
end
For FortiGate B:
config system sdn-connector
edit "AzureSDN"
set type azure
set ha-status enable
set resource-group "fortigateapha"
set subscription-id 00000000-0000-0000-0000-000000000000
config nic
edit "FortiGate-B-NIC1"
config ip
edit "ipconfig1"
set public-ip "FGTAPClusterPublicIP"
next
end
next
end
config route-table
edit "FGTDefaultAPRouteTable"
config route
edit "toDefault"
set next-hop "172.16.136.69"
next
end
next
end
end