(it works smoothly with 4.0 too)

I've created the cluster and the engine is running as an higly available VM in the cluster itself with hosted-engine --deploy but now I want to add a fourth machine to the cluster but I get this error:

 Cannot automatically add the host to cluster Default: Cannot add Host. There is no available server in the cluster to probe the new server.

both if I try to add an host from Ovirt AAdmin GUI or if I try to run "hosted-engine --deploy" on the new machine. Is it possible to have this cluster conf (with the engine running as a VM) with 4 or more machines? What thing should I have to do?

Thanks in advance

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