The resolver configuration file contains information that is read by the resolver routines the first time they are invoked in a process. The file is designed to be human readable and contains a list of name-value pairs that provide various types of resolver information.
The different configuration options are:
nameserver followed by the Internet address (in dot notation) of a name server that the resolver should query. At least one name server should be listed. Up to MAXNS (currently 3) name servers may be listed, in that case the resolver library queries tries them in the order listed. (The algorithm used is to try a name server, and if the query times out, try the next, until out of name servers, then repeat trying all the name servers until a maximum number of retries are made).
domain followed by a domain name, that is the default domain to append to names that do not have a dot in them. This defaults to empty (the root domain).
The name value pair must appear on a single line, and the keyword (e.g. nameserver) must start the line. The value follows the keyword, separated by white space.