host(1) UNIX Programmer's Manual host(1)NAMEhost - query nameserver about domain names and zones
SYNOPSIShost [-v] [-a] [-t querytype] [options] name [server]
host [-v] [-a] [-t querytype] [options] -l zone [server]
host [-v] [options] -H [-D] [-E] [-G] zone
host [-v] [options] -C zone
host [-v] [options] -Ahost
host [options] -x [name ...]
host [options] -X server [name ...]
nslookup
DESCRIPTIONhost looks for information about Internet hosts and domain
names. It gets this information from a set of interconnected
servers that are spread across the world. The information is
stored in the form of "resource records" belonging to
hierarchically organized "zones".
nslookup is only included for compatibility reasons. Do not
use it, it may be removed in the future.
By default, the program simply converts between host names
and Internet addresses. However, with the -t, -a and -v
options, it can be used to find all of the information about
domain names that is maintained by the domain nameserver
system. The information printed consists of various fields
of the associated resource records that were retrieved.
The arguments can be either host names (domain names) or
numeric Internet addresses.
A numeric Internet address consists of four decimal numbers
separated by dots, e.g., 192.16.199.1, representing the four
bytes of the 32-bit address.
The default action is to look up the associated host name.
A host name or domain name consists of component names
(labels) separated by dots, e.g., nikhefh.nikhef.nl
The default action is to look up all of its Internet
addresses.
For single names without a trailing dot, the local domain is
automatically tacked on the end. Thus a user in domain
"nikhef.nl" can say "host nikhapo", and it will actually
look up "nikhapo.nikhef.nl". In all other cases, the name is
tried unchanged. Single names with trailing dot are con-
sidered top-level domain specifications, e.g., "nl."
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Note that the usual lookup convention for any name that does
not end with a trailing dot is to try first with the local
domain appended, and possibly other search domains. This
convention is not used by this program.
The actual suffix to tack on the end is usually the local
domain as specified in the /etc/resolv.conf file, but this
can be overridden. See below for a description of how to
customize the host name lookup.
ARGUMENTS
The first argument is normally the host name (domain name)
for which you want to look up the requested information. If
the first argument is an Internet address, a query is done
on the special "reverse mapping" domain to look up its asso-
ciated host name.
If the -l option is given, the first argument is a domain
zone name for which a complete listing is given. The program
enters a special zone listing mode which has several vari-
ants (see below).
The second argument is optional. It allows you to specify a
particular server to query. If you don't specify this argu-
ment, default servers are used, as defined by the
/etc/resolv.conf file.
EXTENDED SYNTAX
If the -x option is given, it extends the syntax in the
sense that multiple arguments are allowed on the command
line. An optional explicit server must now be specified
using the -X option as it cannot be given as an ordinary
argument any more. The -X option implies -x.
The extended syntax allows no arguments at all, in which
case the arguments will be read from standard input. This
can be a pipe, redirection from a file, or an interactive
terminal. Note that these arguments are the names to be
queried, and not command options. Everything that appears
after a '#' or ';' on an input line will be skipped. Multi-
ple arguments per line are allowed.
OPTIONS
There are a number of options that can be used before the
specified arguments. Some of these options are meaningful
only to the people who maintain the domain database zones.
The first options are the regularly used ones.
-v causes printout to be in a "verbose" format. All
resource record fields are printed. Without this option,
the ttl and class fields are not shown. Also the con-
tents of the "additional information" and "authoritative
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nameservers" sections in the answer from the nameserver
are printed, if present. Normally these sections are
not shown. In addition, the verbose option prints extra
information about the various actions that are taken by
the program. Note that -vv is "very verbose". This gen-
erates a lot of output.
-t querytype
allows you to specify a particular type of resource
record information to be looked up. Supported types are
listed below. The wildcard may be written as either ANY
or *. Types may be given in upper or lower case. The
default is type A for regular lookups, and A, NS, and
PTR for zone listings.
-a is equivalent to -t ANY. Note that this gives you "any-
thing available" (currently cached) and not "all defined
data" if a non-authoritative server is queried.
SPECIAL MODES
The following options put the program in a special mode.
-l zone
generates the listing of an entire zone.
E.g. the command
host-l nikhef.nl
will give a listing of all hosts in the "nikhef.nl"
zone. The -t option is used to filter what information
is extracted, as you would expect. The default is
address information from A records, supplemented with
data from PTR and NS records.
The command
host-Z -a -l nikhef.nl
will give a complete download of the zone data for
"nikhef.nl", in the official master file format.
-H can be specified instead of the -l option. It will print
the count of the unique hostnames (names with an A
record) encountered within the zone. It will not count
pseudo names like "localhost", nor addresses associated
with the zone name itself. Neither are counted the "glue
records" that are necessary to define nameservers for
the zone and its delegated zones.
By default, this option will not print any resource
records.
Combined with the -S option, it will give a complete
statistics survey of the zone.
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The host count may be affected by duplicate hosts (see
below). To compute the most realistic value, subtract
the duplicate host count from the total host count.
-G implies -H, but lists the names of gateway hosts. These
are the hosts that have more than one address. Gateway
hosts are not checked for duplicate addresses.
-E implies -H, but lists the names of extrazone hosts. An
extrazone host in zone "foo.bar" is of the form
"host.xxx.foo.bar" where "xxx.foo.bar" is not defined as
a delegated zone with an NS record. This may be inten-
tional, but also may be an error.
-D implies -H, but lists the names of duplicate hosts.
These are hosts with only one address, which is known to
have been defined also for another host with a different
name, possibly even in a different zone. This may be
intentional, but also may be an error.
-C can be specified instead of the -l option. It causes the
SOA records for the specified zone to be compared as
found at each of the authoritative nameservers for the
zone (as listed in the NS records). Nameserver recursion
is turned off, and it will be checked whether the
answers are really authoritative. If a server cannot
provide an authoritative SOA record, a lame delegation
of the zone to that server is reported. Discrepancies
between the records are reported. Various sanity checks
are performed.
-A enters a special address check mode.
If the first argument is a host name, its addresses will
be retrieved, and for each of the addresses it will be
checked whether they map back to the given host.
If the first argument is a dotted quad Internet address,
its name will be retrieved, and it will be checked
whether the given address is listed among the known
addresses belonging to that host.
If the -A flag is specified along with any zone listing
option, a reverse lookup of the address in each encoun-
tered A record is performed, and it is checked whether
it is registered and maps back to the name of the A
record.
SPECIAL OPTIONS
The following options apply only to the special zone listing
modes.
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Recursively generate zone listings up to this level
deep. Level 1 traverses the parent zone and all of its
delegated zones. Each additional level descends into
another layer of delegated zones.
-S prints statistics about the various types of resource
records found during zone listings, the number of vari-
ous host classifications, the number of delegated zones,
and some total statistics after recursive listings.
-p causes only the primary nameserver of a zone to be con-
tacted for zone transfers during zone listings. Nor-
mally, zone transfers are obtained from any one of the
authoritative servers that responds. The primary
nameserver is obtained from the SOA record of the zone.
If a specific server is given on the command line, this
option will query that server for the desired
nameservers of the zone. This can be used for testing
purposes in case the zone has not been registered yet.
-P prefserver
gives priority for zone transfers to preferred servers
residing in domains given by the comma-separated list
prefserver. The more domain component labels match, the
higher the priority. If this option is not present,
priority is given to servers within your own domain or
parent domains. The order in which NS records are issued
may be unfavorable if they are subject to BIND 4.9
round-robin reshuffling.
-N skipzone
prohibits zone transfers for the zones given by the
comma-separated list skipzone. This may be used during
recursive zone listings when certain zones are known to
contain bogus information which should be excluded from
further processing.
COMMON OPTIONS
The following options can be used in both normal mode and
domain listing mode.
-d turns on debugging. Nameserver transactions are shown
in detail. Note that -dd prints even more debugging out-
put.
-f filename
writes the resource record output to the given logfile
as well as to standard output.
-F filename
same as -f, but exchange the role of stdout and logfile.
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All stdout output (including verbose and debug printout)
goes to the logfile, and stdout gets only the extra
resource record output (so that it can be used in
pipes).
-I chars
suppresses warning messages about illegal domain names
containing invalid characters, by specifying such char-
acters in the string chars. The underscore is a good
candidate.
-i constructs a query for the "reverse mapping" in-
addr.arpa domain in case a numeric (dotted quad) address
was specified. Useful primarily for zone listing mode,
since for numeric regular lookups such query is done
anyway (but with -i you see the actual PTR resource
record outcome).
-n constructs a query for the "reverse mapping" nsap.int
domain in case an nsap address was specified. This can
be used to look up the names associated with nsap
addresses, or to list reverse nsap zones. An nsap
address consists of an even number of hexadecimal
digits, with a maximum of 40, optionally separated by
interspersed dots. An optional prefix "0x" is skipped.
If this option is used, all reverse nsap.int names are
by default printed in forward notation, only to improve
readability. The -Z option forces the output to be in
the official zone file format.
-q be quiet and suppress various warning messages (the ones
preceded by " !!! "). Serious error messages (preceded
by " *** ") are never suppressed.
-T prints the time-to-live values during non-verbose out-
put. By default the ttl is shown only in verbose mode.
-Z prints the selected resource record output in full zone
file format, including trailing dot in domain names,
plus ttl value and class name.
OTHER OPTIONS
The following options are used only in special cir-
cumstances.
-c class
allows you to specify a particular resource record
class. Supported are IN, INTERNET, CS, CSNET, CH, CHAOS,
HS, HESIOD, and the wildcard ANY or *. The default class
is IN.
-e excludes information about names that are not residing
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within the given zone during zone listings, such as some
glue records. For regular queries, it suppresses the
printing of the "additional information" and "authorita-
tive nameserver" sections in the answer from the
nameserver.
-m is equivalent to -t MAILB, which filters any of types
MB, MR, MG, or MINFO. In addition, MR and MG records
will be recursively expanded into MB records.
-o suppresses the resource record output to stdout. Can be
used in combination with the -f option to separate the
resource record output from verbose and debug comments
and error messages.
-r causes nameserver recursion to be turned off in the
request. This means that the contacted nameserver will
return only data it has currently cached in its own
database. It will not ask other servers to retrieve the
information. Note that nameserver recursion is always
turned off when checking SOA records using the -C
option. Authoritative servers should have all relevant
information available.
-R Normally querynames are assumed to be fully qualified
and are tried as such, unless it is a single name, which
is always tried (and only once) in the default domain.
This option simulates the default BIND behavior by qual-
ifying any specified name by repeatedly adding search
domains, with the exception that the search terminates
immediately if the name exists but does not have the
desired querytype. The default search domains are con-
structed from the default domain by repeatedly peeling
off the first component, until a final domain with only
one dot remains.
-s seconds
specifies a new nameserver timeout value. The program
will wait for a nameserver reply in two attempts of this
number of seconds. Normally it does 2 attempts of 5
seconds per nameserver address tried. The actual timeout
algorithm is slightly more complicated, extending the
timeout value dynamically depending on the number of
tries and the number of nameserver addresses.
-u forces the use of virtual circuits (TCP) instead of
datagrams (UDP) when issuing nameserver queries. This is
slower, but potentially more reliable. Note that a vir-
tual circuit is automatically chosen in case a query
exceeds the maximum datagram packet size. Also if a
datagram answer turns out to be truncated, the query is
retried using virtual circuit. A zone transfer is always
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done via a virtual circuit.
-w causes the program to retry forever if the response to a
regular query times out. Normally it will time out after
some 10 seconds per nameserver address tried.
-V prints just the version number of the host program, and
exits.
DEFAULT OPTIONS
Default options and parameters can be preset in an environ-
ment variable HOST_DEFAULTS using the same syntax as on the
command line. They will be evaluated before the command line
arguments.
QUERYTYPES
The following querytypes (resource record types) are sup-
ported. Indicated within parentheses are the various kinds
of data fields.
A Host address (dotted quad)
NS Authoritative nameserver (domain name)
MD Mail destination (domain name)
MF Mail forwarder (domain name)
CNAME Canonical name for an alias (domain name)
SOA Marks the start of a zone of authority (domain
name of primary, domain name of hostmaster,
serial, refresh, retry, expiration, default ttl)
MB Mailbox domain name (domain name)
MG Mail group member (domain name)
MR Mail rename domain name (domain name)
NULL Null resource record (no format or data)
WKS Well-known service description (dotted quad, pro-
tocol name, list of services)
PTR Domain name pointer (domain name)
HINFO Host information (CPU type string, OS type string)
MINFO Mailbox or mail list information (request domain
name, error domain name)
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MX Mail exchanger (preference value, domain name)
TXT Descriptive text (one or more strings)
UINFO User information (string)
UID User identification (number)
GID Group identification (number)
UNSPEC Unspecified binary data (data)
ANY Matches information of any type available.
MAILB Matches any of types MB, MR, MG, or MINFO.
MAILA Matches any of types MD, or MF.
The following types have been defined in RFC 1183, but are
not yet in general use. They are recognized by this program.
RP Responsible person (domain name for MB, domain
name for TXT)
AFSDB AFS database location (type, domain name)
X25 X25 address (address string)
ISDN ISDN address (address string, optional subaddress
string)
RT Route through host (preference value, domain name)
The following types have been defined in RFC 1348, but are
not yet in general use. They are recognized by this program.
RFC 1348 has already been obsoleted by RFC 1637 and RFC
1706, which defines a new experimental usage of NSAP
records. This program has now hooks to manipulate them.
NSAP NSAP address (encoded address)
NSAP-PTR NSAP pointer (domain name)
The following are new types as per RFC 1664 and RFC 1712.
Note that the GPOS type has been withdrawn already, and will
be superseded by the LOC type.
PX X400 to RFC822 mapping (preference value, rfc822
domain, x400 domain)
GPOS Geographical position (longitude string, latitude
string, altitude string)
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The following types have already been reserved in RFC 1700,
but are not yet implemented.
SIG Security signature
KEY Security key
The IP v6 address architecture and DNS extensions are
defined in RFC 2373 and RFC 1886.
AAAA IP v6 address (address spec with colons)
The following type is documented in RFC 1876.
LOC Geographical location (latitude, longitude, alti-
tude, precision)
The following types have been proposed, but are still in
draft.
NXT Next valid record
EID Endpoint identifier
NIMLOC Nimrod locator
SRV Internet service information
ATMA ATM address
NAPTR Naming authority URN
EXAMPLES
A very good summary and validation of an entire zone can be
obtained with the following command:
host-G -S -C -A -L 1 zone
DIAGNOSTICS
FAILURE MESSAGES
The following messages are printed to show the reason of
failure for a particular query. The name of an explicit
server, if specified, may be included. If a special class
was requested, it is also shown.
Nameserver [server] not running
The contacted server host does not have a nameserver
running.
Nameserver [server] not responding
The nameserver at the contacted server host did not give
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a reply within the specified time frame.
Nameserver [server] not reachable
The network route to the intended server host is
blocked.
name does not exist [at server] (Authoritative answer)
The queryname does definitely not exist at all.
name does not exist [at server], try again
The queryname does not exist, but the answer was not
authoritative, so it is still undecided.
name has no type record [at server] (Authoritative answer)
The queryname is valid, but the specified type does not
exist. This status is here returned only in case author-
itative.
name type record currently not present [at server]
The specified type does not exist, but we don't know
whether the queryname is valid or not. The answer was
not authoritative. Perhaps recursion was off, and no
data was cached locally.
name type record not found [at server], try again
Some intermediate failure, e.g., timeout reaching a
nameserver.
name type record not found [at server], server failure
Some explicit nameserver failure to process the query,
due to internal or forwarding errors. This may also be
returned if the zone data has expired at a secondary
server, of when the server is not authoritative for some
class.
name type record not found [at server], no recovery
Some irrecoverable format error, or server refusal.
name type record query refused [by server]
The contacted nameserver explicitly refused to answer
the query. Some nameservers are configured to refuse
zone transfer requests that come from arbitrary clients.
name type record not found [at server]
The exact reason for failure could not be determined.
(This should not happen).
zone has lame delegation to server
If we query a supposedly authoritative nameserver for
the SOA record of a zone, the information should be
available and the answer should be authoritative. If
not, a lame delegation is flagged. This is also done if
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the server turns out not to exist at all. Ditto if we
ask for a zone transfer and the server cannot provide
it.
No nameservers for zone found
It was not possible to retrieve the name of any
nameserver for the desired zone, in order to do a zone
transfer.
No addresses of nameservers for zone found
We got some nameserver names, but it was not possible to
retrieve addresses for any of them.
No nameservers for zone responded
When trying all nameservers in succession to do a zone
transfer, none of them were able or willing to provide
it.
WARNING AND ERROR MESSAGES
Miscellaneous warning messages may be generated. They are
preceded by " !!! " and indicate some non-fatal condition,
usually during the interpretation of the retrieved data.
These messages can be suppressed with the -q command line
option.
Error messages are preceded by " *** " and indicate a seri-
ous problem, such as format errors in the answers to
queries, but also major violations of the specifications.
Those messages cannot be suppressed.
zone has only one nameserver server
When retrieving the nameservers for a zone, it appears
that only one single nameserver exists. This is against
the recommendations.
zone nameserver server is not canonical (realserver)
When retrieving the nameservers for a zone, the name of
the specified server appears not to be canonical. This
may cause serious operational problems. The canonical
name is given between parentheses.
empty zone transfer for zone from server
The zone transfer from the specified server contained no
data, perhaps only the SOA record. This could happen if
we query the victim of a lame delegation which happens
to have the SOA record in its cache.
extraneous NS record for name within zone from server
During a zone transfer, an NS record appears for a name
which is not a delegated subzone of the current zone.
extraneous SOA record for name within zone from server
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During a zone transfer, an SOA record appears for a name
which is not the name of the current zone.
extraneous glue record for name within zone from server
During a zone transfer, a glue record is included for a
name which is not part of the zone or its delegated
subzones. This is done in some older versions of BIND.
It is undesirable since unauthoritative, or even
incorrect, information may be propagated.
incomplete type record for name
When decoding the resource record data from the answer
to a query, not all required data fields were present.
This is frequently the case for HINFO records of which
only one of the two data field is encoded.
name has both NS and A records within zone from server
An A record has been defined for the delegated zone
name. This is signalled only during the transfer of the
parent zone. It is not an error, but the overall
hostcount may be wrong, since the A record is counted as
a host in the parent zone. This A record is not included
in the hostcount of the delegated zone.
name type records have different ttl within zone from server
Resource records of the same name/type/class should have
the same ttl value in zone listings. This is sometimes
not the case, due to the independent definition of glue
records or other information in the parent zone, which
is not kept in sync with the definition in the delegated
zone.
name type record has illegal name
The name of an A or MX record contains invalid charac-
ters. Only alphanumeric characters and hyphen '-' are
valid in components (labels) between dots.
name type host server has illegal name
The name of an NS or MX target host contains invalid
characters. Only alphanumeric characters and hyphen '-'
are valid in components (labels) between dots.
name type host server does not exist
The NS or MX target host server does not exist at all.
In case of NS, a lame delegation of name to server is
flagged.
name type host server has no A record
The NS or MX target host server has no address. In case
of NS, a lame delegation of name to server is flagged.
name type host server is not canonical
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The NS or MX target host server is not a canonical name.
This may cause serious operational problems during
domain data retrieval, or electronic mail delivery.
name address A.B.C.D is not registered
The reverse lookup of the address of an A record failed
in an authoritative fashion. It was not present in the
corresponding in-addr.arpa zone.
name address A.B.C.D maps to realname
The reverse lookup of the address of an A record suc-
ceeded, but it did not map back to the name of the A
record. There may be A records with different names for
the same address. In the reverse in-addr.arpa zone there
is usually only one PTR to the ``official'' host name.
zone SOA record at server is not authoritative
When checking the SOA for a zone at one of its sup-
posedly authoritative nameservers, the SOA information
turns out to be not authoritative. This could be deter-
mined by making a query without nameserver recursion
turned on.
zone SOA primary server is not advertised via NS
The primary nameserver is not among the list of
nameservers retrieved via NS records for the zone. This
is not an error per se, since only publicly accessible
nameservers may be advertised, and others may be behind
a firewall.
zone SOA primary server has illegal name
The name of the primary nameserver contains invalid
characters.
zone SOA hostmaster mailbox has illegal mailbox
The name of the hostmaster mailbox contains invalid
characters. A common mistake is to use an RFC822 email
address with a ``@'', whereas the at-sign should have
been replaced with a dot.
zone SOA serial has high bit set
Although the serial number is an unsigned 32-bit value,
overflow into the high bit can inadvertently occur by
making inappropriate use of the dotted decimal notation
in the zone file. This may lead to synchronization
failures between primary and secondary servers.
zone SOA retry exceeds refresh
A failing refresh would be retried after it is time for
the next refresh.
zone SOA refresh+retry exceeds expire
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The retry after a failing refresh would be done after
the data has already expired.
server1 and server2 have different primary for zone
If the SOA record is different, the zone data is prob-
ably different as well. What you get depends on which
server you happen to query.
server1 and server2 have different hostmaster for zone
If the SOA record is different, the zone data is prob-
ably different as well. What you get depends on which
server you happen to query.
server1 and server2 have different serial for zone
This is usually not an error, but happens during the
period after the primary server has updated its zone
data, but before a secondary performed a refresh.
Nevertheless there could be an error if a mistake has
been made in properly adapting the serial number.
server1 and server2 have different refresh for zone
If the SOA record is different, the zone data is prob-
ably different as well. What you get depends on which
server you happen to query.
server1 and server2 have different retry for zone
If the SOA record is different, the zone data is prob-
ably different as well. What you get depends on which
server you happen to query.
server1 and server2 have different expire for zone
If the SOA record is different, the zone data is prob-
ably different as well. What you get depends on which
server you happen to query.
server1 and server2 have different defttl for zone
If the SOA record is different, the zone data is prob-
ably different as well. What you get depends on which
server you happen to query.
EXIT STATUS
The program returns a zero exit status if the requested
information could be retrieved successfully, or in case zone
listings or SOA checks were performed without any serious
error. Otherwise it returns a non-zero exit status.
ENVIRONMENT
CUSTOMIZING HOST NAME LOOKUP
In general, if the name supplied by the user does not have
any dots in it, a default domain is appended to the end.
This domain is usually defined in the /etc/resolv.conf file.
If not, it is derived by taking the local hostname and
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taking everything after its first dot.
LOCALDOMAIN
The user can override this, and specify a different default
domain, by defining it in the environment variable LOCAL-
DOMAIN.
HOSTALIASES
In addition, the user can supply his own single-word abbre-
viations for host names. They should be in a file consisting
of one line per abbreviation. Each line contains an abbrevi-
ation, whitespace, and then the fully qualified host name.
The name of this file must be specified in the environment
variable HOSTALIASES.
SPECIAL CONSIDERATIONS
The complete set of resource record information for a domain
name is available from an authoritative nameserver only.
Therefore, if you query another server with the "-a" option,
only a subset of the data may be presented, since this
option asks for any data that the latter server currently
knows about, not all data that may possibly exist. Note
that the "-v" option shows whether an answer is authorita-
tive or not.
When listing a zone with the "-l" option, information will
be fetched from authoritative nameservers for that zone.
This is implemented by doing a complete zone transfer and
then filtering out the information that you have asked for.
Note that direct contact with such nameservers must be pos-
sible for this option to work. This option should be used
with caution. Servers may be configured to refuse zone
transfers if they are flooded with requests.
RELATED DOCUMENTATION
rfc883, Domain names - implementation and specification
rfc920, Domain requirements
rfc952, DOD Internet host table specification
rfc974, Mail routing and the domain system
rfc1032, Domain administrators guide
rfc1033, Domain administrators operations guide
rfc1034, Domain names - concepts and facilities
rfc1035, Domain names - implementation and specification
rfc1101, DNS encoding of network names and other types
rfc1123, Requirements for Internet hosts - application
rfc1183, New DNS RR definitions
rfc1348, DNS NSAP RRs
rfc1535, A security problem and proposed correction
rfc1536, Common DNS implementation errors
rfc1537, Common DNS data file configuration errors
rfc1591, Domain Name System structure and delegation
rfc1637, DNS NSAP resource records
MirOS BSD #10-current 961010 16
host(1) UNIX Programmer's Manual host(1)
rfc1664, Using DNS to distribute X.400 address mappings
rfc1700, Assigned numbers
rfc1706, DNS NSAP resource records
rfc1712, DNS encoding of geographical location
rfc1713, Tools for DNS debugging
rfc1794, DNS support for load balancing
rfc1876, Expressing location information in the DNS
rfc1884, IP v6 addressing architecture
rfc1886, DNS extensions to support IP v6
rfc1912, Common DNS operational and configuration errors
rfc1982, Serial number arithmetic
rfc1995, Incremental zone transfer in DNS
rfc1996, Prompt notification of zone changes
AUTHOR
This program is originally from Rutgers University.
Rewritten by Eric Wassenaar, NIKHEF, <e07@nikhef.nl>
SEE ALSOresolv.conf(5), resolver(3)MirOS BSD #10-current 961010 17
