CrushFTP supports high availability mode for Enterprise licenses.\\

This mode will allow for multiple servers to have *[Replication]* between the servers.  A client is valid on all servers, as long as they stick to the server they started on.\\
This can be combined with the *[ServerBeat]* feature to manage a Virtual IP between multiple machines.  This way incoming access points to the VIP, and that VIP will move to a machine that is operational in the event the current machine using the VIP goes down.

Lastly the *[DMZ]* mode can be used placing a DMZ server being controlled by internal an CrushFTP server separated by a firewall allowing only outgoing initiated connections.  A single Internal server can manage multiple DMZ servers.,  But only one internal server should be connected to a DMZ instance, they cannot be cross linked.\\