HOST(1) | General Commands Manual | HOST(1) |
host
— DNS lookup
utility
host |
[-46aCdilrsTVvw ] [-c
class] [-m
flag] [-N
ndots] [-R
number] [-t
type] [-W
wait] name
[server] |
The host
command is a simple utility for
performing DNS lookups. It is normally used to convert names to IP addresses
and vice versa.
name is the domain name that is to be looked
up. It can also be a dotted-decimal IPv4 address or a colon-delimited IPv6
address, in which case host
will by default perform
a reverse lookup for that address. server is an
optional argument which is either the name or IP address of the name server
that host
should query instead of the server or
servers listed in /etc/resolv.conf.
The options are as follows:
-4
-6
-a
-a
option is normally
equivalent to -v
-t
ANY
. It also affects the behaviour of the
-l
list zone option.-C
host
will query the SOA records
for zone name from all the listed authoritative name
servers for that zone. The list of name servers is defined by the NS
records that are found for the zone.-c
classHS
(Hesiod) or CH
(Chaosnet) class resource records.
The default class is IN
(Internet).-d
-v
verbose option.-i
-l
host
command performs a zone
transfer of zone name and prints out the NS, PTR and
address records (A/AAAA).
Together, the -l
-a
options print all records in the zone.
-m
flagrecord
,
usage
, or trace
. You can
specify the -m
option more than once to set
multiple flags.-N
ndots-R
number-r
-r
option enables host
to
mimic the behavior of a name server by making non-recursive queries and
expecting to receive answers to those queries that can be referrals to
other name servers.-s
-T
host
uses UDP when making
queries. The -T
option makes it use a TCP
connection when querying the name server. TCP will be automatically
selected for queries that require it, such as zone transfer (AXFR)
requests.-t
typeCNAME
, NS
,
SOA
, TXT
,
DNSKEY
, AXFR
, etc.
When no query type is specified, host
automatically selects an appropriate query type. By default, it looks
for A, AAAA, and MX records. If the -C
option is
given, queries will be made for SOA records. If
name is a dotted-decimal IPv4 address or
colon-delimited IPv6 address, host
will query
for PTR records.
If a query type of IXFR
is chosen the
starting serial number can be specified by appending an equal followed
by the starting serial number (like -t
IXFR=
12345678).
-V
-v
-d
debug
option.-W
waitBy default, host
will wait for 5
seconds for UDP responses and 10 seconds for TCP connections.
-w
/etc/resolv.conf
Internet Systems Consortium, Inc.
February 7, 2020 | OpenBSD-6.7 |