An NIS+ Server Is Also a Client

An NIS+ server is also an NIS+ client. In fact, before you can set up a machine as a server, you must initialize it as a client. The only exception is the root master server, which has its own unique setup process.

This means that in addition to supporting a domain, a server also belongs to a domain. In other words, by virtue of being a client, a server has a home domain. Its host information is stored in the Hosts table of its home domain, and its DES credentials are stored in the cred table of its home domain. Like other clients, it sends its requests for service to the servers listed in its directory cache.

An important point to remember is that – except for the root domain – a server's home domain is the parent of the domain the server supports:

In other words, a server supports clients in one domain, but is a client of another domain. A server cannot be a client of a domain that it supports, with the exception of the root domain. Because they have no parent domain, the servers that support the root domain belong to the root domain itself.

For example, consider the following namespace:

The chart lists which domain each server supports and which domain it belongs to: