NAME
- dns, dnsquery - domain name service
SYNOPSIS
-
ndb/dns
[
-f dnsfile
] [
-h
] [
-r
] [
-x net
]
ndb/dnsquery [ -x net ] [ 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/cs) 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, dnsquery 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 ALSO
- dns(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) | Rev: Tue Jan 29 13:11:52 GMT 2008 |