For example, information about computers (hosts) is maintained in a hosts and/or ethers table, and information about networks and subnetworks is maintained in a networks and/or netmasks table. Different network management servers may store dissimilar sets of network management tables, with information about different groups of networks and computers maintained on each. Distributed network management environments, like NIS and NIS+, provide mechanisms for sharing management tables across management servers from a central location.
When you delete a computer, subnetwork, or network with AdminSuite, what you are really deleting is the references to these entities in their respective tables. For example, when you delete a network, you are not physically deleting an entire network and all the computers on it, but rather the references to this network in the networks and/or netmasks table on the current management server. The network or computer will still exist, but you will no longer be able to manage it on that management server through AdminSuite or any other tool that makes use of these tables.
The Computers/Networks tool also uses dynamic network and subnetwork containers to represent sets of computers that have IP addresses that do not exist on any defined network or subnetwork in the current management domain. See Displaying Computers, Subnetworks, and Networks for more information about dynamic networks and subnetworks.
Note: The display of dynamic networks is turned off by default. To display dynamic networks, click View->Show Networks and then enable the All Networks option.
The important thing to remember in this context is that you can delete computers, static (real) subnetworks, and static networks, but you cannot delete dynamic networks because, technically, they do not really exist.