diagnose traffictest on a Fortigate 600F with 6.4.14 - not the same as on a 60F/100F?

Dear community and support

I have troubles running "diagnose traffictest" on a Forigate 600F with 6.4.14 - I have no idea how to configure the destination server IP and the port to be used. for the run command

I was using "diagnose traffictest" on Fortigate 60F and 100F running 6.4.14 several times without any issues as I have the commands necessary:

diagnose traffictest client-intf wan1 diagnose traffictest server-intf wan1 diagnose traffictest port 5201 diagnose traffictest run -c <iperf-server-ip> -t 60

However, that does NOT work on a Fortigate 600F with the same version (6.4.14) - that device seems to use different commands and I fail to find any useful documentation (to at least change the server IP, the port to the server and a way to make it run more than 10s).

Any one an idea?