resolver(4) resolver(4) NAME resolver, resolv.conf - host-address resolver configuration file (DNS/NIS) SYNOPSIS /etc/resolv.conf DESCRIPTION This file controls the behavior of then resolver(3N) routines in the C library. It is read by these 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. The keyword and value must appear on a single line, and the keyword (for example, nameserver) must start the line. The value follows the keyword, separated by white space. nameserver Internet address (in dot notation) of a name server that the resolver should query. Up to three of these lines can be specified; 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.) When specifying a nameserver entry for the local machine, use the address 127.0.0.1. 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 hostname returned by gethostname(2); the domain part is taken to be everything after the first `.'. Finally, if the hostname 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 can be changed by listing the desired domain search path following the search keyword with spaces or tabs separating the names. Most resolver queries are attempted using each component of the search path in turn until a match is found. This process can be slow and generates a lot of network traffic if the servers for the listed domains are not local. Queries time out if no server is available for one of the domains. The first item in the list becomes the default domain name; the remaining items are the other domains to search after the default one. The domain and search keywords are mutually exclusive. If more than one instance of these keywords is present, only the first instance is used. sortlist List of preferred networks. The sortlist keyword is followed by a list of network addresses. On each lookup the address list is sorted according to the list of addresses. If multiple addresses match for a single subnet they are presented in the order returned from the server. The format of the items of the list is a dotted quad with an optional slash '/' and netmask. e.g. sortlist 130.155.160.0/255.255.240.0 130.155.0.0 options A list of resolver options. Currently the only supported option is ndots which specifies how many dots need to be in a name for the resolver to attempt to lookup the name as a fully qualified name if the name does not contain a trailing dot. It is followed by a colon ':' and a number. The default is ndots:1. NOTE The hostresorder keyword is now ignored. Resolve order for gethostbyname and gethostbyaddr is now done in the nsswitch.conf file. In previous IRIX releases, the resolv.conf file was in the /usr/etc directory. In order for pre-IRIX5 binaries that use BIND to work correctly, a symbolic link from /etc/resolv.conf must be made to the old name. FILES /etc/resolv.conf SEE ALSO named(1M), gethostbyname(3N), resolver(3N), hostname(5). nsswitch.conf(3); IRIX Admin: Networking and Mail Page 2