To run in local files mode, a machine must have local copies of the TCP/IP configuration files. These files are described in "TCP/IP Configuration Files". The machine should have its own disk, though this is not strictly necessary.
Most servers should run in local file mode. This requirement includes:
Network configuration servers
Name servers supplying NIS, NIS+, or DNS services
Additionally, routers should run in local files mode.
Machines that exclusively function as print servers do not need to run in local files mode. Whether individual hosts should run in local files mode depends on the size of your network.
If you are running a very small network, the amount of work involved in maintaining these files on individual hosts is manageable. If your network serves hundreds of hosts, the task becomes difficult, even with the network divided into a number of administrative subdomains. Thus, for large networks, using local files mode is usually less efficient. On the other hand, because routers and servers must be self-sufficient, they should be configured in local files mode.
RARP - Reverse Address Resolution Protocol (RARP) maps known Ethernet addresses (48 bits) to IP addresses (32 bits), the reverse of ARP. When you run RARP on a network configuration server, this enables hosts running in network client mode to obtain their IP addresses and TCP/IP configuration files from the server. The in.rarpd daemon enables RARP services. Refer to the in.rarpd(1M) man page for complete details.
TFTP - Trivial File Transfer Protocol (TFTP) is an application that transfers files between remote machines. The in.tftpd daemon carries out TFTP services, enabling file transfer between network configuration servers and their network clients.
Network configuration servers can also can function as NFS file servers.
If you are going to configure any hosts as network clients, then you must also configure at least one machine on your network as a network configuration server. If your network is subnetted, then you must have at least one network configuration server for each subnet with network clients.