Maintained by: NLnet Labs
unbound-control(8)               unbound 1.7.0              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
              default 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.

              Remove all bogus data from the cache.

              Remove all negative data  from  the  cache.   This  is  nxdomain
              answers,  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
              address,  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-upstream,     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
              remove 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

       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.

       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.

       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

       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 with ttl zero, because they 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
              request 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
              recursive  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.

              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
              update.  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 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

              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
              additionally,  no data was carried in the answer (making what is
              called  a  NOERROR/NODATA  answer).   These  queries  are   also
              included  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
              answers, 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
              secret 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-

              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                       Mar 15, 2018               unbound-control(8)