What would be the purpose of this standby server? If it will be used for disaster recovery and is to hold the exact and full replica of the production master server catalog, then it has to have the same host name and therefore it needs to be on an isolated network. You can restore a catalog backup from the production server to this standby server to create a replica. Keep in mind that NBU must be installed in the same path and patched to the same Maintenance Pack as the production server.