In order to remotely monitor or administer a server, you’d need some kind of connectivity.
But, you specify “WTHOUT ANY KIND OF NETWORK CONNECTION. EVEN NO LAN OR WAN NOTHING…. “.
What kind of connectivity do you propose? A modem?
Sometimes it is necessary to manage a server without interfering with it’s communication to the environment, or without presenting one. For this need, it is most often necessary to use an IP KVM, or something of the like. This allows “remote” management using the KVM device, while also preventing network connectivity to the device which needs to be managed.