DNS(8)DNS(8)NAME
dns, dnsquery - domain name service
SYNOPSIS
ndb/dns [ -f dnsfile ] [ -h ] [ -r ] [ -x net ]
ndb/dnsquery [ -x net ] [ -s server ] [ address ... ]
DESCRIPTION
Dns is an Internet Domain Name Service (DNS) resolver. By default it
serves a file /net/dns, that clients such as cs(8) write and read to
retrieve network data associated with domain names and Internet
addresses. The -f option specifies the network database that contains
the local DNS data (default: /lib/ndb/local). The -x option specifies
an alternative mount point for the network (default: /net). When
Inferno is running hosted, dns normally uses the host's own DNS
resolver first (via srv(2)), before searching the DNS itself; that way
domain names can be used in Inferno with minimal configuration. The -h
option stops dns from using the host data. In the absence of local
data, by default dns consults the external DNS directly using some
bootstrap data, but if -r is specified and local resolvers are given in
the configuration file, dns(6), dns will query them first for all
addresses, before resorting to external DNS servers.
Dnsquery queries the given server (default: /net/dns) for a translation
of each address and prints the results, one per line. If no address is
given, dnsquery prompts for something to find in the DNS, one per line
on the standard input, of the form:
name [attribute]
where name is the label of something in the DNS, and attribute is one
of its attributes from the list below:
all all data currently known locally for name
cname name for which name is an alias
hinfo host and operating system type
ip for an IP address when name is a domain name
mx mail exchanger
ns for a list of name servers
ptr for the domain name when name is an Internet address
soa statement-of-authority
Dnsquery queries the server for that name/attribute combination and
prints the results, one per line. If an attribute is not given, dns‐
query uses ip if name looks like a domain name, and ptr if it looks
like an Internet address.
FILES
#sdns* service directory
/net/dns
domain name service
/lib/ndb/local
network database
/lib/ndb/dns
DNS bootstrap data
SOURCE
/appl/cmd/ndb/dns.b
/appl/cmd/ndb/dnsquery.b
SEE ALSOdns(6), cs(8)BUGS
Dns does not yet offer an external DNS server, mainly for lack of a
suitable database for local zone data.
DNS(8)
