Linux in a Nutshell, Fourth Edition

Name

host

Synopsis

                  host [options] name [server]

System administration command. Print information about hosts or zones in DNS. Hosts may be IP addresses or hostnames; host converts IP addresses to hostnames by default and appends the local domain to hosts without a trailing dot. Default servers are determined in /etc/resolv.conf. For more information about hosts and zones, read Chapters 1 and 2 of DNS and BIND (O’Reilly).

Options

-a

Same as -t ANY.

-c class

Search for specified resource record class (IN, CH, CHAOS, HS, HESIOD, or ANY). Default is IN.

-d

Verbose output. Same as -v.

-l

Perform reverse lookups for IPv6 addresses using IP6.INT domain and “nibble” labels instead of IP6.ARPA and binary labels.

-n

Perform zone transfer. Same as -t AXFR.

-r

Do not ask contacted server to query other servers, but require only the information that it has cached.

-t type

Look for type entries in the resource record. type may be any recognized query type, such as A, AXFR, CNAME, NS, SOA, SIG, or ANY. If name is a hostname, host will look for A records by default. If name is an IPv4 or IPv6 address, it will look for PTR records.

-v

Verbose. Include all fields from resource record, even time-to-live and class, as well as “additional information” and “authoritative nameservers” (provided by the remote nameserver).

-w

Never give up on queried server.

-C

Display SOA records from all authoritative name servers for the specified zone.

-N n

Consider names with fewer than n dots in them to be relative. ...