FortiManager - Adding FortiGates with IPsec VPNs?

Hi all!

I've added some FortiGates (running 7.0.9) to a FortiManager (running 7.2.2). All appears to be well apart from the IPsec VPN config.

In FortiManager, when I go to VPN Manager > IPsec VPN > Monitor, I can see all the configured tunnels with the gateways and phase 2 names listed.

However, I don't see where this is actually configured in FortiManager?

I get that if setting up and NEW VPN I need to create a VPN community and so on, but how does it work for an existing FortiGate that had existing VPNs that has been added to FMG?

Am I being blind? Sure I don't have to set up the VPNs again from scratch in FMG?

Any advice is very much appreciated! 

Thank in advance.