1unbound(8)                      unbound 1.19.0                      unbound(8)
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NAME

6       unbound - Unbound DNS validating resolver 1.19.0.
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SYNOPSIS

9       unbound [-h] [-d] [-p] [-v] [-c cfgfile]
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DESCRIPTION

12       Unbound is a caching DNS resolver.
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14       It  uses a built in list of authoritative nameservers for the root zone
15       (.), the so called root hints.  On receiving a DNS query  it  will  ask
16       the root nameservers for an answer and will in almost all cases receive
17       a delegation to a top level domain (TLD) authoritative nameserver.   It
18       will  then ask that nameserver for an answer.  It will recursively con‐
19       tinue until an answer is found or no answer  is  available  (NXDOMAIN).
20       For performance and efficiency reasons that answer is cached for a cer‐
21       tain time (the answer's time-to-live or TTL).  A second query  for  the
22       same  name  will  then be answered from the cache.  Unbound can also do
23       DNSSEC validation.
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25       To use a locally running Unbound for resolving put
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27             nameserver 127.0.0.1
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29       into resolv.conf(5).
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31       If authoritative DNS is needed as well using nsd(8), careful  setup  is
32       required  because authoritative nameservers and resolvers are using the
33       same port number (53).
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35       The available options are:
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37       -h     Show the version number and commandline option help, and exit.
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39       -c cfgfile
40              Set the config file with settings for Unbound to read instead of
41              reading  the  file  at  the  default  location, /etc/unbound/un‐
42              bound.conf. The syntax is described in unbound.conf(5).
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44       -d     Debug flag: do not fork into the background, but  stay  attached
45              to  the  console.   This flag will also delay writing to the log
46              file until the thread-spawn time, so that most config and  setup
47              errors  appear  on  stderr. If given twice or more, logging does
48              not switch to the log file or to syslog, but  the  log  messages
49              are printed to stderr all the time.
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51       -p     Don't  use  a pidfile.  This argument should only be used by su‐
52              pervision systems which can ensure that only one instance of Un‐
53              bound will run concurrently.
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55       -v     Increase verbosity. If given multiple times, more information is
56              logged.  This is added to the verbosity (if any) from the config
57              file.
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59       -V     Show the version number and build options, and exit.
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SEE ALSO

62       unbound.conf(5), unbound-checkconf(8), nsd(8).
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AUTHORS

65       Unbound  developers  are mentioned in the CREDITS file in the distribu‐
66       tion.
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70NLnet Labs                       Nov  8, 2023                       unbound(8)
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