unbound-control(8)              unbound 1.13.1              unbound-control(8)

       unbound-control,  unbound-control-setup - Unbound remote server control

       unbound-control [-hq] [-c cfgfile] [-s server] command

       Unbound-control performs remote administration on  the  unbound(8)  DNS
       server.   It  reads the configuration file, contacts the unbound server
       over SSL sends the command and displays the result.

       The available options are:

       -h     Show the version and commandline option help.

       -c cfgfile
              The config file to read with settings.  If not given the default
              config file /usr/local/etc/unbound/unbound.conf is used.

       -s server[@port]
              IPv4  or  IPv6  address of the server to contact.  If not given,
              the address is read from the config file.

       -q     quiet, if the option is given it does not print anything  if  it
              works ok.

       There are several commands that the server understands.

       start  Start  the  server.  Simply  execs unbound(8).  The unbound exe-
              cutable is searched for in the PATH set in the environment.   It
              is  started  with  the config file specified using -c or the de-
              fault config file.

       stop   Stop the server. The server daemon exits.

       reload Reload the server. This flushes the cache and reads  the  config
              file fresh.

       verbosity number
              Change  verbosity  value  for  logging. Same values as verbosity
              keyword in unbound.conf(5).  This new setting  lasts  until  the
              server is issued a reload (taken from config file again), or the
              next verbosity control command.

              Reopen the logfile, close and open it.  Useful  for  logrotation
              to  make  the  daemon release the file it is logging to.  If you
              are using syslog it will attempt to close and  open  the  syslog
              (which may not work if chrooted).

       stats  Print statistics. Resets the internal counters to zero, this can
              be controlled using the statistics-cumulative config  statement.
              Statistics are printed with one [name]: [value] per line.

              Peek at statistics. Prints them like the stats command does, but
              does not reset the internal counters to zero.

       status Display server status. Exit code 3 if not running  (the  connec-
              tion to the port is refused), 1 on error, 0 if running.

       local_zone name type
              Add  new  local  zone with name and type. Like local-zone config
              statement.  If the zone already exists, the type is  changed  to
              the given argument.

       local_zone_remove name
              Remove  the  local  zone with the given name.  Removes all local
              data inside it.  If the zone does not exist,  the  command  suc-

       local_data RR data...
              Add  new  local data, the given resource record. Like local-data
              config statement, except for when no covering zone  exists.   In
              that case this remote control command creates a transparent zone
              with the same name as this record.  This command is not good  at
              returning detailed syntax errors.

       local_data_remove name
              Remove  all RR data from local name.  If the name already has no
              items, nothing happens.  Often results in NXDOMAIN for the  name
              (in  a static zone), but if the name has become an empty nonter-
              minal (there is still data in domain  names  below  the  removed
              name), NOERROR nodata answers are the result for that name.

              Add  local  zones  read  from stdin of unbound-control. Input is
              read per line, with name space type on a line.  For  bulk  addi-

              Remove  local zones read from stdin of unbound-control. Input is
              one name per line. For bulk removals.

              Add local data RRs read from stdin of unbound-control. Input  is
              one RR per line. For bulk additions.

              Remove  local data RRs read from stdin of unbound-control. Input
              is one name per line. For bulk removals.

              The contents of the cache is printed in a text format to stdout.
              You can redirect it to a file to store the cache in a file.

              The  contents  of the cache is loaded from stdin.  Uses the same
              format as dump_cache uses.  Loading the cache with old, or wrong
              data can result in old or wrong data returned to clients.  Load-
              ing data into the cache in this way is supported in order to aid
              with debugging.

       lookup name
              Print  to  stdout the name servers that would be used to look up
              the name specified.

       flush name
              Remove the name from the cache. Removes the types A,  AAAA,  NS,
              SOA, CNAME, DNAME, MX, PTR, SRV and NAPTR.  Because that is fast
              to do. Other record types can be  removed  using  flush_type  or

       flush_type name type
              Remove the name, type information from the cache.

       flush_zone name
              Remove all information at or below the name from the cache.  The
              rrsets and key entries are removed so that new lookups  will  be
              performed.  This needs to walk and inspect the entire cache, and
              is a slow operation.  The entries are set to expired in the  im-
              plementation  of  this  command (so, with serve-expired enabled,
              it'll serve that information but schedule a prefetch for new in-

              Remove all bogus data from the cache.

              Remove  all  negative data from the cache.  This is nxdomain an-
              swers, nodata answers and servfail answers.   Also  removes  bad
              key  entries  (which  could  be  due to failed lookups) from the
              dnssec key cache, and iterator last-resort lookup failures  from
              the rrset cache.

              Reset statistics to zero.

              Drop  the  queries  that  are  worked  on.  Stops working on the
              queries that the server is working on now.  The cache  is  unaf-
              fected.   No  reply  is  sent for those queries, probably making
              those users request again later.   Useful  to  make  the  server
              restart  working  on queries with new settings, such as a higher
              verbosity level.

              Show what is worked on.  Prints all queries that the  server  is
              currently  working  on.   Prints  the  time that users have been
              waiting.  For internal requests, no time is printed.   And  then
              prints  out the module status.  This prints the queries from the
              first thread, and not queries that are being serviced from other

       flush_infra all|IP
              If all then entire infra cache is emptied.  If a specific IP ad-
              dress, the entry for that address is removed from the cache.  It
              contains EDNS, ping and lameness data.

              Show the contents of the infra cache.

       set_option opt: val
              Set  the  option to the given value without a reload.  The cache
              is therefore not flushed.  The option must end with  a  ':'  and
              whitespace  must be between the option and the value.  Some val-
              ues may not have an effect if set this way, the new  values  are
              not  written  to the config file, not all options are supported.
              This is different from the set_option call in libunbound,  where
              all values work because unbound has not been initialized.

              The  values that work are: statistics-interval, statistics-cumu-
              lative,      do-not-query-localhost,       harden-short-bufsize,
              harden-large-queries,    harden-glue,    harden-dnssec-stripped,
              harden-below-nxdomain,      harden-referral-path,      prefetch,
              prefetch-key,  log-queries,  hide-identity,  hide-version, iden-
              tity, version, val-log-level,  val-log-squelch,  ignore-cd-flag,
              add-holddown,  del-holddown, keep-missing, tcp-upstream, ssl-up-
              stream, max-udp-size,  ratelimit,  ip-ratelimit,  cache-max-ttl,
              cache-min-ttl, cache-max-negative-ttl.

       get_option opt
              Get  the  value  of  the option.  Give the option name without a
              trailing ':'.  The value is printed.  If the value is "",  noth-
              ing  is printed and the connection closes.  On error 'error ...'
              is printed (it gives a syntax error  on  unknown  option).   For
              some  options  a  list  of values, one on each line, is printed.
              The options are shown from the  config  file  as  modified  with
              set_option.   For  some  options an override may have been taken
              that does not show up with this command, not results  from  e.g.
              the  verbosity  and  forward  control commands.  Not all options
              work,  see  list_stubs,  list_forwards,   list_local_zones   and
              list_local_data for those.

              List the stub zones in use.  These are printed one by one to the
              output.  This includes the root hints in use.

              List the forward zones in use.  These are printed zone  by  zone
              to the output.

              List the zones with domain-insecure.

              List  the  local  zones  in use.  These are printed one per line
              with zone type.

              List the local data  RRs  in  use.   The  resource  records  are

       insecure_add zone
              Add  a domain-insecure for the given zone, like the statement in
              unbound.conf.  Adds to the running unbound without affecting the
              cache  contents (which may still be bogus, use flush_zone to re-
              move it), does not affect the config file.

       insecure_remove zone
              Removes domain-insecure for the given zone.

       forward_add [+i] zone addr ...
              Add a new forward zone to running unbound.  With +i option  also
              adds  a  domain-insecure  for  the zone (so it can resolve inse-
              curely if you have a DNSSEC root  trust  anchor  configured  for
              other  names).   The  addr  can be IP4, IP6 or nameserver names,
              like forward-zone config in unbound.conf.

       forward_remove [+i] zone
              Remove a forward zone from running unbound.  The +i also removes
              a domain-insecure for the zone.

       stub_add [+ip] zone addr ...
              Add  a  new  stub  zone to running unbound.  With +i option also
              adds a domain-insecure for the zone.  With +p the stub  zone  is
              set to prime, without it it is set to notprime.  The addr can be
              IP4, IP6 or nameserver names, like the stub-zone config  in  un-

       stub_remove [+i] zone
              Remove  a stub zone from running unbound.  The +i also removes a
              domain-insecure for the zone.

       forward [off | addr ... ]
              Setup forwarding mode.  Configures  if  the  server  should  ask
              other upstream nameservers, should go to the internet root name-
              servers itself, or show the current config.  You could pass  the
              nameservers after a DHCP update.

              Without  arguments the current list of addresses used to forward
              all queries to is printed.  On startup this  is  from  the  for-
              ward-zone  "."  configuration.   Afterwards it shows the status.
              It prints off when no forwarding is used.

              If off is passed, forwarding is  disabled  and  the  root  name-
              servers  are  used.  This can be used to avoid to avoid buggy or
              non-DNSSEC supporting nameservers returned from DHCP.   But  may
              not work in hotels or hotspots.

              If  one or more IPv4 or IPv6 addresses are given, those are then
              used to forward queries to.  The  addresses  must  be  separated
              with spaces.  With '@port' the port number can be set explicitly
              (default port is 53 (DNS)).

              By default the forwarder information from the  config  file  for
              the  root "." is used.  The config file is not changed, so after
              a reload these changes are gone.  Other forward zones  from  the
              config file are not affected by this command.

       ratelimit_list [+a]
              List  the  domains  that  are ratelimited.  Printed one per line
              with current estimated qps and qps limit from config.   With  +a
              it  prints  all  domains, not just the ratelimited domains, with
              their estimated qps.  The ratelimited domains  return  an  error
              for uncached (new) queries, but cached queries work as normal.

       ip_ratelimit_list [+a]
              List  the  ip  addresses  that are ratelimited.  Printed one per
              line with current estimated qps and qps limit from config.  With
              +a  it  prints all ips, not just the ratelimited ips, with their
              estimated qps.  The ratelimited ips are dropped before  checking
              the cache.

              List  the  auth zones that are configured.  Printed one per line
              with a status, indicating if the zone is expired and current se-
              rial number.

       auth_zone_reload zone
              Reload  the  auth  zone  from zonefile.  The zonefile is read in
              overwriting the current contents of the zone  in  memory.   This
              changes  the  auth zone contents itself, not the cache contents.
              Such cache contents exists if you set unbound to  validate  with
              for-upstream yes and that can be cleared with flush_zone zone.

       auth_zone_transfer zone
              Transfer  the  auth  zone  from master.  The auth zone probe se-
              quence is started, where the masters are probed to see  if  they
              have  an updated zone (with the SOA serial check).  And then the
              zone is transferred for a newer zone version.

       rpz_enable zone
              Enable the RPZ zone if it had previously been disabled.

       rpz_enable zone
              Disable the RPZ zone.

       view_list_local_zones view
              list_local_zones for given view.

       view_local_zone view name type
              local_zone for given view.

       view_local_zone_remove view name
              local_zone_remove for given view.

       view_list_local_data view
              list_local_data for given view.

       view_local_data view RR data...
              local_data for given view.

       view_local_data_remove view name
              local_data_remove for given view.

       view_local_datas_remove view
              Remove a list of local_data for given view from stdin. Like  lo-

       view_local_datas view
              Add  a  list  of local_data for given view from stdin.  Like lo-

       The unbound-control program exits with status code 1  on  error,  0  on

       The  setup requires a self-signed certificate and private keys for both
       the server and  client.   The  script  unbound-control-setup  generates
       these  in  the  default run directory, or with -d in another directory.
       If you change the access control permissions on the key files  you  can
       decide  who can use unbound-control, by default owner and group but not
       all users.  Run the script under the same username as you have  config-
       ured  in  unbound.conf  or  as root, so that the daemon is permitted to
       read the files, for example with:
           sudo -u unbound unbound-control-setup
       If you have not configured a username in unbound.conf,  the  keys  need
       read  permission  for  the  user  credentials under which the daemon is
       started.  The script preserves private keys present in  the  directory.
       After  running  the  script  as  root,  turn  on  control-enable in un-

       The stats command shows a number of statistic counters.

              number of queries received by thread

              number of queries rate limited by thread

              number of queries that were successfully answered using a  cache

              number of queries that needed recursive processing

              number  of queries that were encrypted and successfully decapsu-
              lated by dnscrypt.

              number of queries that were requesting dnscrypt certificates.

              number of queries received on dnscrypt port that were  cleartext
              and not a request for certificates.

              number  of  request  that  were  neither  cleartext,  not  valid
              dnscrypt messages.

              number of cache prefetches performed.  This number  is  included
              in  cachehits, as the original query had the unprefetched answer
              from cache, and resulted in recursive processing, taking a  slot
              in  the  requestlist.   Not part of the recursivereplies (or the
              histogram thereof) or cachemiss, as a cache response was sent.

              number of replies that served an expired cache entry.

              The number of replies sent to queries that needed recursive pro-
              cessing.  Could  be smaller than threadX.num.cachemiss if due to
              timeouts no replies were sent for some queries.

              The average number of requests in the  internal  recursive  pro-
              cessing  request list on insert of a new incoming recursive pro-
              cessing query.

              Maximum size attained by the internal recursive  processing  re-
              quest list.

              Number  of requests in the request list that were overwritten by
              newer entries. This happens if there is a flood of queries  that
              recursive processing and the server has a hard time.

              Queries  that  were  dropped  because the request list was full.
              This happens if a flood of queries  need  recursive  processing,
              and the server can not keep up.

              Current  size of the request list, includes internally generated
              queries (such as priming queries and glue lookups).

              Current size of the request list, only the requests from  client

              Average  time  it  took  to answer queries that needed recursive
              processing. Note that queries that were answered from the  cache
              are not in this average.

              The median of the time it took to answer queries that needed re-
              cursive processing.  The median  means  that  50%  of  the  user
              queries  were  answered  in less than this time.  Because of big
              outliers (usually queries to non responsive servers), the  aver-
              age  can be bigger than the median.  This median has been calcu-
              lated by interpolation from a histogram.

              The currently held tcp buffers for incoming connections.  A spot
              value  on  the  time of the request.  This helps you spot if the
              incoming-num-tcp buffers are full.

              summed over threads.

              summed over threads.

              summed over threads.

              summed over threads.

              summed over threads.

              summed over threads.

              summed over threads.

              summed over threads.

              summed over threads.

              summed over threads.

              averaged over threads.

              the maximum of the thread requestlist.max values.

              summed over threads.

              summed over threads.

              summed over threads.

              averaged over threads.

              summed over threads.

              current time in seconds since 1970.

              uptime since server boot in seconds.

              time since last statistics printout, in seconds.

              Memory in bytes in use by the RRset cache.

              Memory in bytes in use by the message cache.

              Memory in bytes in use by the dnscrypt shared secrets cache.

              Memory in bytes in use by the dnscrypt nonce cache.

              Memory in bytes in use by the iterator module.

              Memory in bytes in use by the validator module. Includes the key
              cache and negative cache.

              Memory  in bytes in used by the TCP and TLS stream wait buffers.
              These are answers waiting to be written back to the clients.

              Memory in bytes used by the  HTTP/2  query  buffers.  Containing
              (partial) DNS queries waiting for request stream completion.

              Memory  in bytes used by the HTTP/2 response buffers. Containing
              DNS responses waiting to be written back to the clients.

              Shows a histogram, summed over all threads. Every element counts
              the recursive queries whose reply time fit between the lower and
              upper bound.  Times larger  or  equal  to  the  lowerbound,  and
              smaller than the upper bound.  There are 40 buckets, with bucket
              sizes doubling.

              The total number of queries over all threads with query type  A.
              Printed  for  the  other  query  types as well, but only for the
              types for which queries were received, thus =0 entries are omit-
              ted for brevity.

              Number of queries with query types 256-65535.

              The total number of queries over all threads with query class IN
              (internet).  Also printed for other classes (such as CH  (CHAOS)
              sometimes used for debugging), or NONE, ANY, used by dynamic up-
              date.  num.query.class.other is printed for classes 256-65535.

              The total number of queries over all threads with  query  opcode
              QUERY.  Also printed for other opcodes, UPDATE, ...

              Number  of  queries that were made using TCP towards the unbound

              Number of queries that the unbound server made using TCP  outgo-
              ing towards other servers.

              Number  of  queries that were made using TLS towards the unbound
              server.  These are also counted in  num.query.tcp,  because  TLS
              uses TCP.

              Number  of  TLS  session resumptions, these are queries over TLS
              towards the unbound server where the  client  negotiated  a  TLS
              session resumption key.

              Number of queries that were made using HTTPS towards the unbound
              server.   These  are   also   counted   in   num.query.tcp   and
              num.query.tls, because HTTPS uses TLS and TCP.

              Number  of queries that were made using IPv6 towards the unbound

              The number of queries that had the RD flag set  in  the  header.
              Also  printed  for  flags  QR, AA, TC, RA, Z, AD, CD.  Note that
              queries with flags QR, AA or TC may have been  rejected  because
              of that.

              number of queries that had an EDNS OPT record present.

              number  of  queries  that  had  an  EDNS  OPT record with the DO
              (DNSSEC OK) bit set.  These queries are  also  included  in  the
              num.query.edns.present number.

              The  number  of  queries that are turned away from being send to
              nameserver due to ratelimiting.

              The number of dnscrypt queries that did not find a shared secret
              in  the  cache.  The can be use to compute the shared secret hi-

              The number of dnscrypt queries that found a  nonce  hit  in  the
              nonce cache and hence are considered a query replay.

              The  number of answers to queries, from cache or from recursion,
              that had the return code NXDOMAIN. Also printed  for  the  other
              return codes.

              The number of answers to queries that had the pseudo return code
              nodata.  This means the actual return code was NOERROR, but  ad-
              ditionally,  no  data  was carried in the answer (making what is
              called a NOERROR/NODATA answer).  These  queries  are  also  in-
              cluded  in the num.answer.rcode.NOERROR number.  Common for AAAA
              lookups when an A record exists, and no AAAA.

              Number of answers that were secure.  The answer  validated  cor-
              rectly.   The  AD  bit  might have been set in some of these an-
              swers, where the client signalled (with DO  or  AD  bit  in  the
              query) that they were ready to accept the AD bit in the answer.

              Number  of  answers  that were bogus.  These answers resulted in
              SERVFAIL to the client because the answer failed validation.

              The number of rrsets marked bogus by the  validator.   Increased
              for every RRset inspection that fails.

              Number  of  queries  that  were  refused or dropped because they
              failed the access control settings.

              Replies that were unwanted or unsolicited.  Could have been ran-
              dom  traffic, delayed duplicates, very late answers, or could be
              spoofing attempts.  Some low level of late answers  and  delayed
              duplicates  are to be expected with the UDP protocol.  Very high
              values could indicate a threat (spoofing).

              The number of items (DNS replies) in the message cache.

              The number of RRsets in the rrset cache.  This  includes  rrsets
              used  by  the messages in the message cache, but also delegation

              The number of items in the infra cache.  These are IP  addresses
              with their timing and protocol support information.

              The  number  of  items in the key cache.  These are DNSSEC keys,
              one item per delegation point, and their validation status.

              The number of items in the shared secret cache. These  are  pre-
              computed shared secrets for a given client public key/server se-
              cret key pair. Shared secrets are CPU intensive and  this  cache
              allows  unbound to avoid recomputing the shared secret when mul-
              tiple dnscrypt queries are sent from the same client.

              The number of items in the client nonce  cache.  This  cache  is
              used  to  prevent dnscrypt queries replay. The client nonce must
              be unique for each client public  key/server  secret  key  pair.
              This cache should be able to host QPS * `replay window` interval
              keys to prevent replay of a query during  `replay  window`  sec-

              The  number  of  queries  answered from auth-zone data, upstream
              queries.  These queries would otherwise  have  been  sent  (with
              fallback enabled) to the internet, but are now answered from the
              auth zone.

              The number of queries for  downstream  answered  from  auth-zone
              data.   These  queries are from downstream clients, and have had
              an answer from the data in the auth zone.

              The number of queries answered using cached  NSEC  records  with
              NODATA  RCODE.   These queries would otherwise have been sent to
              the internet, but are now answered using cached data.

              The number of queries answered using cached  NSEC  records  with
              NXDOMAIN RCODE.  These queries would otherwise have been sent to
              the internet, but are now answered using cached data.

              Number of queries that got an answer that contained EDNS  client
              subnet data.

              Number  of  queries  answered from the edns client subnet cache.
              These are counted as cachemiss by the main counters, but hit the
              client  subnet  specific  cache,  after getting processed by the
              edns client subnet module.

              Number of queries answered using configured RPZ policy, per  RPZ
              action  type.  Possible actions are: nxdomain, nodata, passthru,
              drop, local_data, disabled, and cname_override.

              unbound configuration file.

              directory with private keys (unbound_server.key and unbound_con-
              trol.key)  and  self-signed certificates (unbound_server.pem and

       unbound.conf(5), unbound(8).

NLnet Labs                       Feb  9, 2021               unbound-control(8)