A DNS name space must have one ore more root domain name servers that are authoritative for the root domain.
If your network is connected to the Internet, your root domain server exists at the root domain Internet site and all you have to do is provide that site's Internet IP addresses in your cache file as explained in "Internet Root Domain Server".
If your network is not connected to the Internet, you must set up primary and secondary name servers in the root-level domain on your local network as explained in "Non-Internet Root Domain Server". This is so that all domains in your network have a consistent authoritative server to which to refer; otherwise, machines may not be able to resolve queries.
The information that identifies the root domain name servers is stored in a cache file. This manual and most Solaris sites call this file named.ca. (Other common names for this file are: root.cache, named.root, or db.cache.) Each server's boot file contains a record identifying the file that holds the root domain name server information.
If your site is connected to the Internet, your DNS name server's boot files must point to a common cache file (usually called named.ca) that identifies the root domain name servers. A template for this file may be obtained from InterNIC registration services via:
Anonymous FTP. The FTP site is: ftp.rs.internic.net. The file name is: /domain/named.root.
Gopher. The Gopher site is: rs.internic.net. The file is: named.root which can be found under the InterNIC Registration Services menu, InterNIC Registration Archives submenu.
If you are naming your DNS files according to the conventions in this manual, you need to move this file to /var/named/named.ca.
If your site is not connected to the Internet, you must set up one or more of your servers to perform as root domain name servers. The boot files of all DNS name servers on your network must point to a common cache file (usually called named.ca) that identifies the root domain name servers. You then create a cache file that identifies your root name servers.
Since a single machine can be the primary domain name server for more than one machine, the easiest way to create a root domain name server is to have the server for your highest level domain also be the server for the logical "." domain.
For example, suppose you have given your network the domain name solo. The DNS master name server is dnsmaster.solo.(with a trailing dot). In this case, you would make dnsmaster the root master server for the "." domain.
If your network has more than one top-level domain, the root domain server name should be the primary name server for all top-level domains. For example, if your network is divided into two separate, non-hierarchal domains named solo and private, the same server must be root master server for both of them. Following the example above that would mean that dnsmaster.solo. is root domain master for both the solo and the private domains.