home *** CD-ROM | disk | FTP | other *** search
- RESOLVER(5) December 14, 1989
-
-
- NAME
- resolver \- resolver configuration file
-
- SYNOPSIS
- /etc/resolv.conf
-
- DESCRIPTION
- The resolver is a set of routines in the C library (resolv (3))
- that provide access to the Internet Domain Name System. The resolver
- configuration file contains information that is read by the resolver routines
- the first time they are invoked by a process. The file is designed to be
- human readable and contains a list of keywords with values that provide
- various types of resolver information.
-
- On a normally configured system this file should not be necessary.
- The only name server to be queried will be on the local machine, the domain
- name is determined from the host name, and the domain search path is
- constructed from the domain name.
-
- The different configuration options are:
-
- • nameserver
- Internet address (in dot notation) of a name server that the resolver
- should query.
- Up to MAXNS (currently 3) name servers may be listed, one per keyword. If
- there are multiple servers, the resolver library queries them in the order
- listed. If no nameserver entries are present, the default is to use the
- name server on the local machine. (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
- Local domain name.
- Most queries for names within this domain can use short names relative to
- the local domain. If no domain entry is present, the domain is determined
- from the local host name returned by gethostname; the domain part is taken
- to be everything after the first `.´.
- Finally, if the host name does not contain a domain part, the root domain
- is assumed.
-
- • search
- Search list for host-name lookup.
- The search list is normally determined from the local domain name; by
- default, it begins with the local domain name, then successive parent
- domains that have at least two components in their names. This may be
- changed by listing the desired domain search path following the search
- keyword with spaces or tabs separating the names. Most resolver queries
- will be attempted using each component of the search path in turn until
- a match is found.
- Note that this process may be slow and will generate a lot of network
- traffic if the servers for the listed domains are not local, and that
- queries will time out if no server is available for one of the domains.
-
- The search list is currently limited to six domains with a total of 256
- characters.
-
- The domain and search keywords are mutually exclusive. If more than one
- instance of these keywords is present, the last instance will override.
-
- The keyword and value 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.
-
- FILES
- /etc/resolv.conf
-
- SEE ALSO
- gethostbyname(3N), resolver(3), hostname(7), named(8)
-
- Name Server Operations Guide for BIND
-