host — DNS lookup utility
host [-aCdlnrsTwv] [-c ] [class-N ] [ndots-R ] [number-t ] [type-W ] [wait-m ] [flag-4] [-6] {name} [server]
host is a simple utility for performing DNS lookups. It is normally used to convert names to IP addresses and vice versa. When no arguments or options are given, host prints a short summary of its command line arguments and options.
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 -a (all) option is equivalent to setting the
-v option and asking host to make
a query of type ANY.
When the -C option is used, host
will attempt to display 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.
The -c option instructs to make a DNS query of class
class. This can be used to lookup
Hesiod or
Chaosnet class resource records. The default class is IN (Internet).
Verbose output is generated by host when
the
-d or -v option is used. The two
options are equivalent. They have been provided for backwards
compatibility. In previous versions, the -d option
switched on debugging traces and -v enabled verbose
output.
List mode is selected by the -l option. This makes
host perform a zone transfer for zone
name. Transfer the zone printing out
the NS, PTR
and address records (A/AAAA). If combined with -a
all records will be printed.
The -i
option specifies that reverse lookups of IPv6 addresses should
use the IP6.INT domain as defined in RFC1886.
The default is to use IP6.ARPA.
The -N option sets the number of dots that have to be
in name for it to be considered
absolute. The
default value is that defined using the ndots statement in
/etc/resolv.conf, or 1 if no ndots
statement is
present. Names with fewer dots are interpreted as relative names and
will be searched for in the domains listed in the search
or domain directive in
/etc/resolv.conf.
The number of UDP retries for a lookup can be changed with the
-R option. number
indicates
how many times host will repeat a query
that does
not get answered. The default number of retries is 1. If
number is negative or zero, the
number of
retries will default to 1.
Non-recursive queries can be made via the -r option.
Setting this option clears the RD — recursion
desired — bit in the query which host makes.
This should mean that the name server receiving the query will not
attempt to resolve name. The
-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 are usually
referrals to other name servers.
By default, 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.
The -4 option forces host to only
use IPv4 query transport. The -6 option forces
host to only use IPv6 query transport.
The -t option is used to select the query type.
type can be any recognized query
type: CNAME,
NS, SOA, SIG, KEY, 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, but if the
-C option was given, queries will be made for SOA
records, and 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 (e.g. -t IXFR=12345678).
The time to wait for a reply can be controlled through the
-W and -w options. The
-W option makes host
wait for
wait seconds. If wait
is less than one, the wait interval is set to one second. When the
-w option is used, host
will
effectively wait forever for a reply. The time to wait for a response
will be set to the number of seconds given by the hardware's maximum
value for an integer quantity.
The -s option tells host
not to send the query to the next nameserver
if any server responds with a SERVFAIL response, which is the
reverse of normal stub resolver behavior.
The -m can be used to set the memory usage debugging
flags
record, usage and
trace.
If host has been built with IDN (internationalized
domain name) support, it can accept and display non-ASCII domain names.
host appropriately converts character encoding of
domain name before sending a request to DNS server or displaying a
reply from the server.
If you'd like to turn off the IDN support for some reason, defines
the IDN_DISABLE environment variable.
The IDN support is disabled if the variable is set when
host runs.
host [-aCdlnrsTwv] [-c ] [class-N ] [ndots-R ] [number-t ] [type-W ] [wait-m ] [flag-4] [-6] [-v] [-V] {name} [server]
The -V option causes host
to print the version number and exit.
host
d40 1
a40 1
host
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a46 1
IPv6 address, in which case host will by
d51 1
a51 1
the name or IP address of the name server that host
d57 1
a57 1
-v option and asking host to make
d61 1
a61 1
When the -C option is used, host
d75 1
a75 1
Verbose output is generated by host when
d85 1
a85 1
host perform a zone transfer for zone
d113 1
a113 1
how many times host will repeat a query
d123 1
a123 1
desired — bit in the query which host makes.
d126 1
a126 1
-r option enables host
d133 1
a133 1
By default, host uses UDP when making
d140 1
a140 1
The -4 option forces host to only
d142 1
a142 1
host to only use IPv6 query transport.
d149 1
a149 1
host automatically selects an appropriate
d155 1
a155 1
address or colon-delimited IPv6 address, host will
d163 1
a163 1
-W option makes host
d167 1
a167 1
-w option is used, host
d174 1
a174 1
The -s option tells host
d186 1
a186 1
The -V option causes host
d190 2
a191 2
host [-aCdlnrsTwv] [-c ] [class-N ] [ndots-R ] [number-t ] [type-W ] [wait-m ] [flag-4] [-6] [-v] [-V] {name} [server]
The -V option causes host
to print the version number and exit.
host
d40 1
a40 1
host
d46 1
a46 1
IPv6 address, in which case host will by
d51 1
a51 1
the name or IP address of the name server that host
d57 1
a57 1
-v option and asking host to make
d61 1
a61 1
When the -C option is used, host
d75 1
a75 1
Verbose output is generated by host when
d85 1
a85 1
host perform a zone transfer for zone
d113 1
a113 1
how many times host will repeat a query
d123 1
a123 1
desired — bit in the query which host makes.
d126 1
a126 1
-r option enables host
d133 1
a133 1
By default, host uses UDP when making
d140 1
a140 1
The -4 option forces host to only
d142 1
a142 1
host to only use IPv6 query transport.
d149 1
a149 1
host automatically selects an appropriate
d155 1
a155 1
address or colon-delimited IPv6 address, host will
d163 1
a163 1
-W option makes host
d167 1
a167 1
-w option is used, host
d174 1
a174 1
The -s option tells host
d186 1
a186 1
The -V option causes host
d190 2
a191 2
host [-aCdlnrsTwv] [-c ] [class-N ] [ndots-R ] [number-t ] [type-W ] [wait-m ] [flag-4] [-6] [-v] [-V] {name} [server]
The -V option causes host
to print the version number and exit.
host
d40 1
a40 1
host
d46 1
a46 1
IPv6 address, in which case host will by
d51 1
a51 1
the name or IP address of the name server that host
d57 1
a57 1
-v option and asking host to make
d61 1
a61 1
When the -C option is used, host
d75 1
a75 1
Verbose output is generated by host when
d85 1
a85 1
host perform a zone transfer for zone
d113 1
a113 1
how many times host will repeat a query
d123 1
a123 1
desired — bit in the query which host makes.
d126 1
a126 1
-r option enables host
d133 1
a133 1
By default, host uses UDP when making
d140 1
a140 1
The -4 option forces host to only
d142 1
a142 1
host to only use IPv6 query transport.
d149 1
a149 1
host automatically selects an appropriate
d155 1
a155 1
address or colon-delimited IPv6 address, host will
d163 1
a163 1
-W option makes host
d167 1
a167 1
-w option is used, host
d174 1
a174 1
The -s option tells host
d186 1
a186 1
The -V option causes host
d190 2
a191 2
host [-aCdlnrsTwv] [-c ] [class-N ] [ndots-R ] [number-t ] [type-W ] [wait-m ] [flag-4] [-6] [-v] [-V] {name} [server]
The -V option causes host
to print the version number and exit.
host [-aCdlnrsTwv] [-c ] [class-N ] [ndots-R ] [number-t ] [type-W ] [wait-m ] [flag-4] [-6] [-v] [-V] {name} [server]
The -V option causes host
to print the version number and exit.
host [-aCdlnrsTwv] [-c ] [class-N ] [ndots-R ] [number-t ] [type-W ] [wait-m ] [flag-4] [-6] [-v] [-V] {name} [server]
The -V option causes host
to print the version number and exit.
host
d40 1
a40 1
host
d46 1
a46 1
IPv6 address, in which case host will by
d51 1
a51 1
the name or IP address of the name server that host
d57 1
a57 1
-v option and asking host to make
d61 1
a61 1
When the -C option is used, host
d75 1
a75 1
Verbose output is generated by host when
d85 1
a85 1
host perform a zone transfer for zone
d113 1
a113 1
how many times host will repeat a query
d123 1
a123 1
desired — bit in the query which host makes.
d126 1
a126 1
-r option enables host
d133 1
a133 1
By default, host uses UDP when making
d140 1
a140 1
The -4 option forces host to only
d142 1
a142 1
host to only use IPv6 query transport.
d149 1
a149 1
host automatically selects an appropriate
d155 1
a155 1
address or colon-delimited IPv6 address, host will
d163 1
a163 1
-W option makes host
d167 1
a167 1
-w option is used, host
d174 1
a174 1
The -s option tells host
d186 1
a186 1
The -V option causes host
d190 2
a191 2
host
d40 1
a40 1
host
d46 1
a46 1
IPv6 address, in which case host will by
d51 1
a51 1
the name or IP address of the name server that host
d57 1
a57 1
-v option and asking host to make
d61 1
a61 1
When the -C option is used, host
d75 1
a75 1
Verbose output is generated by host when
d85 1
a85 1
host perform a zone transfer for zone
d113 1
a113 1
how many times host will repeat a query
d123 1
a123 1
desired — bit in the query which host makes.
d126 1
a126 1
-r option enables host
d133 1
a133 1
By default, host uses UDP when making
d140 1
a140 1
The -4 option forces host to only
d142 1
a142 1
host to only use IPv6 query transport.
d149 1
a149 1
host automatically selects an appropriate
d155 1
a155 1
address or colon-delimited IPv6 address, host will
d163 1
a163 1
-W option makes host
d167 1
a167 1
-w option is used, host
d174 1
a174 1
The -s option tells host
d186 1
a186 1
The -V option causes host
d190 2
a191 2
host — DNS lookup utility
d29 1 a29 4
host
[-aCdlnrsTwv]
[-c ]
[class-N ]
[ndots-R ]
[number-t ]
[type-W ]
[wait-m ]
[flag-4]
[-6]
[-v]
[-V]
{name}
[server]
host d42 1 a42 2
name is the domain name that is to be
d54 138
a191 213
Use IPv4 only for query transport.
See also the -6 option.
Use IPv6 only for query transport.
See also the -4 option.
"All". The -a option is normally equivalent
to -v -t .
It also affects the behaviour of the ANY-l
list zone option.
classQuery class: This can be used to lookup HS (Hesiod) or CH (Chaosnet) class resource records. The default class is IN (Internet).
Check consistency: 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.
Print debugging traces.
Equivalent to the -v verbose option.
Obsolete. Use the IP6.INT domain for reverse lookups of IPv6 addresses as defined in RFC1886 and deprecated in RFC4159. The default is to use IP6.ARPA as specified in RFC3596.
List zone:
The 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.
ndots
The number of dots that have to be
in name for it to be considered
absolute. The default value is that defined using the
ndots statement in /etc/resolv.conf,
or 1 if no ndots statement is present. Names with fewer
dots are interpreted as relative names and will be
searched for in the domains listed in
the search or domain directive
in /etc/resolv.conf.
Non-recursive query:
Setting this option clears the RD (recursion desired) bit
in the query. This should mean that the name server
receiving the query will not attempt to
resolve name.
The -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.
number
Number of retries for UDP queries:
If number is negative or zero, the
number of retries will default to 1. The default value is 1.
Do not send the query to the next nameserver if any server responds with a SERVFAIL response, which is the reverse of normal stub resolver behavior.
type
Query type:
The type argument can be any
recognized query type: CNAME, 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
TCP:
By default, 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.
flag
Memory usage debugging: the flag can
be record, usage,
or trace. You can specify
the -m option more than once to set
multiple flags.
Verbose output.
Equivalent to the -d debug option.
Print the version number and exit.
Wait forever: The query timeout is set to the maximum possible.
See also the -W option.
wait
Timeout: Wait for up to wait
seconds for a reply. If wait is
less than one, the wait interval is set to one second.
By default, host will wait for 5 seconds for UDP responses and 10 seconds for TCP connections.
See also the -w option.
host — DNS lookup utility
d29 1 a29 4
host
[-aCdlnrsTwv]
[-c ]
[class-N ]
[ndots-R ]
[number-t ]
[type-W ]
[wait-m ]
[flag-4]
[-6]
[-v]
[-V]
{name}
[server]
host d42 1 a42 2
name is the domain name that is to be
d54 138
a191 213
Use IPv4 only for query transport.
See also the -6 option.
Use IPv6 only for query transport.
See also the -4 option.
"All". The -a option is normally equivalent
to -v -t .
It also affects the behaviour of the ANY-l
list zone option.
classQuery class: This can be used to lookup HS (Hesiod) or CH (Chaosnet) class resource records. The default class is IN (Internet).
Check consistency: 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.
Print debugging traces.
Equivalent to the -v verbose option.
Obsolete. Use the IP6.INT domain for reverse lookups of IPv6 addresses as defined in RFC1886 and deprecated in RFC4159. The default is to use IP6.ARPA as specified in RFC3596.
List zone:
The 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.
ndots
The number of dots that have to be
in name for it to be considered
absolute. The default value is that defined using the
ndots statement in /etc/resolv.conf,
or 1 if no ndots statement is present. Names with fewer
dots are interpreted as relative names and will be
searched for in the domains listed in
the search or domain directive
in /etc/resolv.conf.
Non-recursive query:
Setting this option clears the RD (recursion desired) bit
in the query. This should mean that the name server
receiving the query will not attempt to
resolve name.
The -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.
number
Number of retries for UDP queries:
If number is negative or zero, the
number of retries will default to 1. The default value is 1.
Do not send the query to the next nameserver if any server responds with a SERVFAIL response, which is the reverse of normal stub resolver behavior.
type
Query type:
The type argument can be any
recognized query type: CNAME, 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
TCP:
By default, 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.
flag
Memory usage debugging: the flag can
be record, usage,
or trace. You can specify
the -m option more than once to set
multiple flags.
Verbose output.
Equivalent to the -d debug option.
Print the version number and exit.
Wait forever: The query timeout is set to the maximum possible.
See also the -W option.
wait
Timeout: Wait for up to wait
seconds for a reply. If wait is
less than one, the wait interval is set to one second.
By default, host will wait for 5 seconds for UDP responses and 10 seconds for TCP connections.
See also the -w option.
host
d40 1
a40 1
host
d46 1
a46 1
IPv6 address, in which case host will by
d51 1
a51 1
the name or IP address of the name server that host
d57 1
a57 1
-v option and asking host to make
d61 1
a61 1
When the -C option is used, host
d75 1
a75 1
Verbose output is generated by host when
d85 1
a85 1
host perform a zone transfer for zone
d113 1
a113 1
how many times host will repeat a query
d123 1
a123 1
desired — bit in the query which host makes.
d126 1
a126 1
-r option enables host
d133 1
a133 1
By default, host uses UDP when making
d140 1
a140 1
The -4 option forces host to only
d142 1
a142 1
host to only use IPv6 query transport.
d149 1
a149 1
host automatically selects an appropriate
d155 1
a155 1
address or colon-delimited IPv6 address, host will
d163 1
a163 1
-W option makes host
d167 1
a167 1
-w option is used, host
d174 1
a174 1
The -s option tells host
d186 1
a186 1
The -V option causes host
d190 2
a191 2
host — DNS lookup utility
d29 1 a29 4
host
[-aCdlnrsTwv]
[-c ]
[class-N ]
[ndots-R ]
[number-t ]
[type-W ]
[wait-m ]
[flag-4]
[-6]
[-v]
[-V]
{name}
[server]
host d42 1 a42 2
name is the domain name that is to be
d54 138
a191 213
Use IPv4 only for query transport.
See also the -6 option.
Use IPv6 only for query transport.
See also the -4 option.
"All". The -a option is normally equivalent
to -v -t .
It also affects the behaviour of the ANY-l
list zone option.
classQuery class: This can be used to lookup HS (Hesiod) or CH (Chaosnet) class resource records. The default class is IN (Internet).
Check consistency: 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.
Print debugging traces.
Equivalent to the -v verbose option.
Obsolete. Use the IP6.INT domain for reverse lookups of IPv6 addresses as defined in RFC1886 and deprecated in RFC4159. The default is to use IP6.ARPA as specified in RFC3596.
List zone:
The 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.
ndots
The number of dots that have to be
in name for it to be considered
absolute. The default value is that defined using the
ndots statement in /etc/resolv.conf,
or 1 if no ndots statement is present. Names with fewer
dots are interpreted as relative names and will be
searched for in the domains listed in
the search or domain directive
in /etc/resolv.conf.
Non-recursive query:
Setting this option clears the RD (recursion desired) bit
in the query. This should mean that the name server
receiving the query will not attempt to
resolve name.
The -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.
number
Number of retries for UDP queries:
If number is negative or zero, the
number of retries will default to 1. The default value is 1.
Do not send the query to the next nameserver if any server responds with a SERVFAIL response, which is the reverse of normal stub resolver behavior.
type
Query type:
The type argument can be any
recognized query type: CNAME, 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
TCP:
By default, 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.
flag
Memory usage debugging: the flag can
be record, usage,
or trace. You can specify
the -m option more than once to set
multiple flags.
Verbose output.
Equivalent to the -d debug option.
Print the version number and exit.
Wait forever: The query timeout is set to the maximum possible.
See also the -W option.
wait
Timeout: Wait for up to wait
seconds for a reply. If wait is
less than one, the wait interval is set to one second.
By default, host will wait for 5 seconds for UDP responses and 10 seconds for TCP connections.
See also the -w option.
host
d40 1
a40 1
host
d46 1
a46 1
IPv6 address, in which case host will by
d51 1
a51 1
the name or IP address of the name server that host
d57 1
a57 1
-v option and asking host to make
d61 1
a61 1
When the -C option is used, host
d75 1
a75 1
Verbose output is generated by host when
d85 1
a85 1
host perform a zone transfer for zone
d113 1
a113 1
how many times host will repeat a query
d123 1
a123 1
desired — bit in the query which host makes.
d126 1
a126 1
-r option enables host
d133 1
a133 1
By default, host uses UDP when making
d140 1
a140 1
The -4 option forces host to only
d142 1
a142 1
host to only use IPv6 query transport.
d149 1
a149 1
host automatically selects an appropriate
d155 1
a155 1
address or colon-delimited IPv6 address, host will
d163 1
a163 1
-W option makes host
d167 1
a167 1
-w option is used, host
d174 1
a174 1
The -s option tells host
d186 1
a186 1
The -V option causes host
d190 2
a191 2
host — DNS lookup utility
d29 1 a29 4
host
[-aCdlnrsTwv]
[-c ]
[class-N ]
[ndots-R ]
[number-t ]
[type-W ]
[wait-m ]
[flag-4]
[-6]
[-v]
[-V]
{name}
[server]
host d42 1 a42 2
name is the domain name that is to be
d54 138
a191 213
Use IPv4 only for query transport.
See also the -6 option.
Use IPv6 only for query transport.
See also the -4 option.
"All". The -a option is normally equivalent
to -v -t .
It also affects the behaviour of the ANY-l
list zone option.
classQuery class: This can be used to lookup HS (Hesiod) or CH (Chaosnet) class resource records. The default class is IN (Internet).
Check consistency: 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.
Print debugging traces.
Equivalent to the -v verbose option.
Obsolete. Use the IP6.INT domain for reverse lookups of IPv6 addresses as defined in RFC1886 and deprecated in RFC4159. The default is to use IP6.ARPA as specified in RFC3596.
List zone:
The 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.
ndots
The number of dots that have to be
in name for it to be considered
absolute. The default value is that defined using the
ndots statement in /etc/resolv.conf,
or 1 if no ndots statement is present. Names with fewer
dots are interpreted as relative names and will be
searched for in the domains listed in
the search or domain directive
in /etc/resolv.conf.
Non-recursive query:
Setting this option clears the RD (recursion desired) bit
in the query. This should mean that the name server
receiving the query will not attempt to
resolve name.
The -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.
number
Number of retries for UDP queries:
If number is negative or zero, the
number of retries will default to 1. The default value is 1.
Do not send the query to the next nameserver if any server responds with a SERVFAIL response, which is the reverse of normal stub resolver behavior.
type
Query type:
The type argument can be any
recognized query type: CNAME, 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
TCP:
By default, 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.
flag
Memory usage debugging: the flag can
be record, usage,
or trace. You can specify
the -m option more than once to set
multiple flags.
Verbose output.
Equivalent to the -d debug option.
Print the version number and exit.
Wait forever: The query timeout is set to the maximum possible.
See also the -W option.
wait
Timeout: Wait for up to wait
seconds for a reply. If wait is
less than one, the wait interval is set to one second.
By default, host will wait for 5 seconds for UDP responses and 10 seconds for TCP connections.
See also the -w option.
host — DNS lookup utility
d29 1 a29 4
host
[-aCdlnrsTwv]
[-c ]
[class-N ]
[ndots-R ]
[number-t ]
[type-W ]
[wait-m ]
[flag-4]
[-6]
[-v]
[-V]
{name}
[server]
host d42 1 a42 2
name is the domain name that is to be
d54 138
a191 213
Use IPv4 only for query transport.
See also the -6 option.
Use IPv6 only for query transport.
See also the -4 option.
"All". The -a option is normally equivalent
to -v -t .
It also affects the behaviour of the ANY-l
list zone option.
classQuery class: This can be used to lookup HS (Hesiod) or CH (Chaosnet) class resource records. The default class is IN (Internet).
Check consistency: 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.
Print debugging traces.
Equivalent to the -v verbose option.
Obsolete. Use the IP6.INT domain for reverse lookups of IPv6 addresses as defined in RFC1886 and deprecated in RFC4159. The default is to use IP6.ARPA as specified in RFC3596.
List zone:
The 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.
ndots
The number of dots that have to be
in name for it to be considered
absolute. The default value is that defined using the
ndots statement in /etc/resolv.conf,
or 1 if no ndots statement is present. Names with fewer
dots are interpreted as relative names and will be
searched for in the domains listed in
the search or domain directive
in /etc/resolv.conf.
Non-recursive query:
Setting this option clears the RD (recursion desired) bit
in the query. This should mean that the name server
receiving the query will not attempt to
resolve name.
The -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.
number
Number of retries for UDP queries:
If number is negative or zero, the
number of retries will default to 1. The default value is 1.
Do not send the query to the next nameserver if any server responds with a SERVFAIL response, which is the reverse of normal stub resolver behavior.
type
Query type:
The type argument can be any
recognized query type: CNAME, 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
TCP:
By default, 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.
flag
Memory usage debugging: the flag can
be record, usage,
or trace. You can specify
the -m option more than once to set
multiple flags.
Verbose output.
Equivalent to the -d debug option.
Print the version number and exit.
Wait forever: The query timeout is set to the maximum possible.
See also the -W option.
wait
Timeout: Wait for up to wait
seconds for a reply. If wait is
less than one, the wait interval is set to one second.
By default, host will wait for 5 seconds for UDP responses and 10 seconds for TCP connections.
See also the -w option.
-4]
| [-6]
]
@
1.1.1.9
log
@Changes since 9.10.5-P2:
--- 9.10.7 released ---
--- 9.10.7rc2 released ---
4904. [bug] Temporarily revert change #4859. [GL #124]
--- 9.10.7rc1 released ---
4889. [func] Warn about the use of old root keys without the new
root key being present. Warn about dlv.isc.org's
key being present. Warn about both managed and
trusted root keys being present. [RT #43670]
4888. [test] Initialize sockets correctly in sample-update so
that the nsupdate system test will run on Windows.
[RT #47097]
4886. [doc] Document dig -u in manpage. [RT #47150]
4885. [security] update-policy rules that otherwise ignore the name
field now require that it be set to "." to ensure
that any type list present is properly interpreted.
[RT #47126]
4882. [bug] Address potential memory leak in
dns_update_signaturesinc. [RT #47084]
4881. [bug] Only include dst_openssl.h when OpenSSL is required.
[RT #47068]
4879. [bug] dns_rdata_caa:value_len field was too small.
[RT #47086]
--- 9.10.7b1 released ---
4876. [bug] Address deadlock with accessing a keytable. [RT #47000]
4874. [bug] Wrong time display when reporting new keywarntime.
[RT #47042]
4872. [bug] Don't permit loading meta RR types such as TKEY
from master files. [RT #47009]
4871. [bug] Fix configure glitch in detecting stdatomic.h
support on systems with multiple compilers.
[RT #46959]
4870. [test] Update included ATF library to atf-0.21 preserving
the ATF tool. [RT #46967]
4869. [bug] Address some cases where NULL with zero length could
be passed to memmove which is undefined behaviour and
can lead to bad optimisation. [RT #46888]
4867. [cleanup] Normalize rndc on/off commands (validation and
querylog) so they accept the same synonyms
for on/off (yes/no, true/false, enable/disable).
Thanks to Tony Finch. [RT #47022]
4866. [port] DST library initialization verifies MD5 (when MD5
was not disabled) and SHA-1 hash and HMAC support.
[RT #46764]
4863. [bug] Fix various other bugs reported by Valgrind's
memcheck tool. [RT #46978]
4862. [bug] The rdata flags for RRSIG were not being properly set
when constructing a rdataslab. [RT #46978]
4861. [bug] The isc_crc64 unit test was not endian independent.
[RT #46973]
4860. [bug] isc_int8_t should be signed char. [RT #46973]
4859. [bug] A loop was possible when attempting to validate
unsigned CNAME responses from secure zones;
this caused a delay in returning SERVFAIL and
also increased the chances of encountering
CVE-2017-3145. [RT #46839]
4858. [security] Addresses could be referenced after being freed
in resolver.c, causing an assertion failure.
(CVE-2017-3145) [RT #46839]
4857. [bug] Maintain attach/detach semantics for event->db,
event->node, event->rdataset and event->sigrdataset
in query.c. [RT #46891]
4856. [bug] 'rndc zonestatus' reported the wrong underlying type
for a inline slave zone. [RT #46875]
4852. [bug] Add REQUIRE's and INSIST's to isc_time_formattimestamp,
isc_time_formathttptimestamp, isc_time_formatISO8601.
[RT #46892]
4851. [port] Support using kyua as well as atf-run to run the unit
tests. [RT #46853]
4846. [test] Adjust timing values in runtime system test. Address
named.pid removal races in runtime system test.
[RT #46800]
4844. [test] Address memory leaks in libatf-c. [RT #46798]
4843. [bug] dnssec-signzone free hashlist on exit. [RT #46791]
4842. [bug] Conditionally compile opensslecdsa_link.c to avoid
warnings about unused function. [RT #46790]
4841. [bug] Address -fsanitize=undefined warnings. [RT #46786]
4840. [test] Add tests to cover fallback to using ZSK on inactive
KSK. [RT #46787]
4839. [bug] zone.c:zone_sign was not properly determining
if there were active KSK and ZSK keys for
a algorithm when update-check-ksk is true
(default) leaving records unsigned with one or
more DNSKEY algorithms. [RT #46774]
4838. [bug] zone.c:add_sigs was not properly determining
if there were active KSK and ZSK keys for
a algorithm when update-check-ksk is true
(default) leaving records unsigned with one or
more DNSKEY algorithms. [RT #46754]
4837. [bug] dns_update_signatures{inc} (add_sigs) was not
properly determining if there were active KSK and
ZSK keys for a algorithm when update-check-ksk is
true (default) leaving records unsigned when there
were multiple DNSKEY algorithms for the zone.
[RT #46743]
4836. [bug] Zones created using "rndc addzone" could
temporarily fail to inherit an "allow-transfer"
ACL that had been configured in the options
statement. [RT #46603]
4833. [bug] isc_event_free should check that the event is not
linked when called. [RT #46725]
4832. [bug] Events were not being removed from zone->rss_events.
[RT #46725]
4831. [bug] Convert the RRSIG expirytime to 64 bits for
comparisions in diff.c:resign. [RT #46710]
4830. [bug] Failure to configure ATF when requested did not cause
an error in top-level configure script. [RT #46655]
4829. [bug] isc_heap_delete did not zero the index value when
the heap was created with a callback to do that.
[RT #46709]
4827. [misc] Add a precommit check script util/checklibs.sh
[RT #46215]
4826. [cleanup] Prevent potential build failures in bin/confgen/ and
bin/named/ when using parallel make. [RT #46648]
4823. [test] Refactor reclimit system test to improve its
reliability and speed. [RT #46632]
4822. [bug] Use resign_sooner in dns_db_setsigningtime. [RT #46473]
4821. [bug] When resigning ensure that the SOA's expire time is
always later that the resigning time of other records.
[RT #46473]
4820. [bug] dns_db_subtractrdataset should transfer the resigning
information to the new header. [RT #46473]
4819. [bug] Fully backout the transaction when adding a RRset
to the resigning / removal heaps fails. [RT #46473]
4818. [test] The logfileconfig system test could intermittently
report false negatives on some platforms. [RT #46615]
4817. [cleanup] Use DNS_NAME_INITABSOLUTE and DNS_NAME_INITNONABSOLUTE.
[RT #45433]
4816. [bug] Don't use a common array for storing EDNS options
in DiG as it could fill up. [RT #45611]
4815. [bug] rbt_test.c:insert_and_delete needed to call
dns_rbt_addnode instead of dns_rbt_addname. [RT #46553]
4814. [cleanup] Use AS_HELP_STRING for consistent help text. [RT #46521]
4812. [bug] Minor improvements to stability and consistency of code
handling managed keys. [RT #46468]
4810. [test] The chain system test failed if the IPv6 interfaces
were not configured. [RT #46508]
4809. [port] Check at configure time whether -latomic is needed
for stdatomic.h. [RT #46324]
4805. [bug] TCP4Active and TCP6Active weren't being updated
correctly. [RT #46454]
4804. [port] win32: access() does not work on directories as
required by POSIX. Supply a alternative in
isc_file_isdirwritable. [RT #46394]
4803. [bug] Backport fix for RT #46055 from RT #46267. [RT #46430]
4792. [bug] Fix map file header correctness check. [RT #38418]
4791. [doc] Fixed outdated documentation about export libraries.
[RT #46341]
4790. [bug] nsupdate could trigger a require when sending a
update to the second address of the server.
[RT #45731]
4788. [cleanup] When using "update-policy local", log a warning
when an update matching the session key is received
from a remote host. [RT #46213]
4787. [cleanup] Turn nsec3param_salt_totext() into a public function,
dns_nsec3param_salttotext(), and add unit tests for it.
[RT #46289]
4783. [test] dnssec: 'check that NOTIFY is sent at the end of
NSEC3 chain generation failed' required more time
on some machines for the IXFR to complete. [RT #46388]
4781. [maint] B.ROOT-SERVERS.NET is now 199.9.14.201. [RT #45889]
4780. [bug] When answering ANY queries, don't include the NS
RRset in the authority section if it was already
in the answer section. [RT #44543]
4777. [cleanup] Removed a redundant call to configure_view_acl().
[RT #46369]
4774. [bug] -4]
| [-6]
]
@
1.1.1.9.2.1
log
@Sync with HEAD
@
text
@@
1.1.1.1.2.1
log
@file host.html was added on branch jym-xensuspend on 2009-05-13 18:49:15 +0000
@
text
@d1 212
@
1.1.1.1.2.2
log
@Sync with HEAD.
Second commit. See http://mail-index.netbsd.org/source-changes/2009/05/13/msg221222.html
@
text
@a0 212
host — DNS lookup utility
host [-aCdlnrsTwv] [-c ] [class-N ] [ndots-R ] [number-t ] [type-W ] [wait-m ] [flag-4] [-6] {name} [server]
host is a simple utility for performing DNS lookups. It is normally used to convert names to IP addresses and vice versa. When no arguments or options are given, host prints a short summary of its command line arguments and options.
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 -a (all) option is equivalent to setting the
-v option and asking host to make
a query of type ANY.
When the -C option is used, host
will attempt to display 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.
The -c option instructs to make a DNS query of class
class. This can be used to lookup
Hesiod or
Chaosnet class resource records. The default class is IN (Internet).
Verbose output is generated by host when
the
-d or -v option is used. The two
options are equivalent. They have been provided for backwards
compatibility. In previous versions, the -d option
switched on debugging traces and -v enabled verbose
output.
List mode is selected by the -l option. This makes
host perform a zone transfer for zone
name. Transfer the zone printing out
the NS, PTR
and address records (A/AAAA). If combined with -a
all records will be printed.
The -i
option specifies that reverse lookups of IPv6 addresses should
use the IP6.INT domain as defined in RFC1886.
The default is to use IP6.ARPA.
The -N option sets the number of dots that have to be
in name for it to be considered
absolute. The
default value is that defined using the ndots statement in
/etc/resolv.conf, or 1 if no ndots
statement is
present. Names with fewer dots are interpreted as relative names and
will be searched for in the domains listed in the search
or domain directive in
/etc/resolv.conf.
The number of UDP retries for a lookup can be changed with the
-R option. number
indicates
how many times host will repeat a query
that does
not get answered. The default number of retries is 1. If
number is negative or zero, the
number of
retries will default to 1.
Non-recursive queries can be made via the -r option.
Setting this option clears the RD — recursion
desired — bit in the query which host makes.
This should mean that the name server receiving the query will not
attempt to resolve name. The
-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 are usually
referrals to other name servers.
By default, 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.
The -4 option forces host to only
use IPv4 query transport. The -6 option forces
host to only use IPv6 query transport.
The -t option is used to select the query type.
type can be any recognized query
type: CNAME,
NS, SOA, SIG, KEY, 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, but if the
-C option was given, queries will be made for SOA
records, and 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 (e.g. -t IXFR=12345678).
The time to wait for a reply can be controlled through the
-W and -w options. The
-W option makes host
wait for
wait seconds. If wait
is less than one, the wait interval is set to one second. When the
-w option is used, host
will
effectively wait forever for a reply. The time to wait for a response
will be set to the number of seconds given by the hardware's maximum
value for an integer quantity.
The -s option tells host
not to send the query to the next nameserver
if any server responds with a SERVFAIL response, which is the
reverse of normal stub resolver behavior.
The -m can be used to set the memory usage debugging
flags
record, usage and
trace.
If host has been built with IDN (internationalized
domain name) support, it can accept and display non-ASCII domain names.
host appropriately converts character encoding of
domain name before sending a request to DNS server or displaying a
reply from the server.
If you'd like to turn off the IDN support for some reason, defines
the IDN_DISABLE environment variable.
The IDN support is disabled if the variable is set when
host runs.