Like i learned now, thats just possible if you have bought the Appliance, when youre using the GCE or the GSE you cant use the ssh connection from Greenbonel.
But you can make a normal ssh tunnel to your other system and can start there gvm-cli
(In my way its doesnt help me because i wantet to connect from check mk to greenbone, but over the ssh tunnel i dont get all variables from check_mk to greenbone)
The SSH connection is not very special. It’s just a nice solution build into our appliances. But we are not going to give advises on howto setup this connection type.