Maintained by: NLnet Labs
unbound-control(8)               unbound 1.5.6              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.

              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 inited.

              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,     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.

       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 that were successfully answered using a cache

              number of queries that needed recursive processing

              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.

              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.

              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.

              If sbrk(2) is available, an estimate of the  heap  size  of  the
              program  in  number  of bytes. Close to the total memory used by
              the program, as reported by top and ps.  Could be wrong  if  the
              OS allocates memory non-contiguously.

              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 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 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.

              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                       Oct 20, 2015               unbound-control(8)