zScaler VPN with dynamic ip

Hi everybody,

we're running several Fortigate (the problem case is a 60F, running 7.4)

We build GRE tunnels to zScaler for every location and set default route to zScaler.

This works perfect :)

On some locations we do not have a static ip address.

So my problem is, I can't get it work.

On zScaler site i can choose FQDN Auth, then specify a user@domain.com and a PSK.

But how do i need to config it on fortigate site?

thanks in advance.