Provided by: unbound_1.20.0-1ubuntu2.1_amd64 
NAME
unbound-control, unbound-control-setup - Unbound remote server control utility.
SYNOPSIS
unbound-control [-hq] [-c cfgfile] [-s server] command
DESCRIPTION
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
/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.
COMMANDS
There are several commands that the server understands.
start Start the server. Simply execs unbound(8). The Unbound executable 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.
reload_keep_cache
Reload the server but try to keep the RRset and message cache if (re)configuration
allows for it. That means the caches sizes and the number of threads must not
change between reloads.
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.
log_reopen
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.
stats_noreset
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 connection 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 succeeds.
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.
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 nonterminal (there is still data in domain names below the
removed name), NOERROR nodata answers are the result for that name.
local_zones
Add local zones read from stdin of unbound-control. Input is read per line, with
name space type on a line. For bulk additions.
local_zones_remove
Remove local zones read from stdin of unbound-control. Input is one name per line.
For bulk removals.
local_datas
Add local data RRs read from stdin of unbound-control. Input is one RR per line.
For bulk additions.
local_datas_remove
Remove local data RRs read from stdin of unbound-control. Input is one name per
line. For bulk removals.
dump_cache
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.
load_cache
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. Loading 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, NAPTR, SVCB and HTTPS. Because that is fast to do. Other record
types can be removed using flush_type or flush_zone.
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 implementation of this command (so, with serve-expired enabled, it'll serve
that information but schedule a prefetch for new information).
flush_bogus
Remove all bogus data from the cache.
flush_negative
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.
flush_stats
Reset statistics to zero.
flush_requestlist
Drop the queries that are worked on. Stops working on the queries that the server
is working on now. The cache is unaffected. 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.
dump_requestlist
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 threads.
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.
dump_infra
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 values 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-cumulative,
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, identity, 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 "", nothing 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_stubs
List the stub zones in use. These are printed one by one to the output. This
includes the root hints in use.
list_forwards
List the forward zones in use. These are printed zone by zone to the output.
list_insecure
List the zones with domain-insecure.
list_local_zones
List the local zones in use. These are printed one per line with zone type.
list_local_data
List the local data RRs in use. The resource records are printed.
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 [+it] 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 insecurely 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. The +t option sets it
to use tls upstream, like forward-tls-upstream: yes.
forward_remove [+i] zone
Remove a forward zone from running Unbound. The +i also removes a domain-insecure
for the zone.
stub_add [+ipt] 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 unbound.conf. The +t option sets it to use tls upstream, like
stub-tls-upstream: yes.
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 nameservers 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 forward-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 nameservers 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_auth_zones
List the auth zones that are configured. Printed one per line with a status,
indicating if the zone is expired and current serial number. Configured RPZ zones
are included.
auth_zone_reload zone
Reload the auth zone (or RPZ 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 (or RPZ zone) from master. The auth zone probe sequence 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_disable 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 local_datas_remove.
view_local_datas view
Add a list of local_data for given view from stdin. Like local_datas.
EXIT CODE
The unbound-control program exits with status code 1 on error, 0 on success.
SET UP
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 configured 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
unbound.conf.
STATISTIC COUNTERS
The stats command shows a number of statistic counters.
threadX.num.queries
number of queries received by thread
threadX.num.queries_ip_ratelimited
number of queries rate limited by thread
threadX.num.queries_cookie_valid
number of queries with a valid DNS Cookie by thread
threadX.num.queries_cookie_client
number of queries with a client part only DNS Cookie by thread
threadX.num.queries_cookie_invalid
number of queries with an invalid DNS Cookie by thread
threadX.num.cachehits
number of queries that were successfully answered using a cache lookup
threadX.num.cachemiss
number of queries that needed recursive processing
threadX.num.dnscrypt.crypted
number of queries that were encrypted and successfully decapsulated by dnscrypt.
threadX.num.dnscrypt.cert
number of queries that were requesting dnscrypt certificates.
threadX.num.dnscrypt.cleartext
number of queries received on dnscrypt port that were cleartext and not a request
for certificates.
threadX.num.dnscrypt.malformed
number of request that were neither cleartext, not valid dnscrypt messages.
threadX.num.prefetch
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.
threadX.num.expired
number of replies that served an expired cache entry.
threadX.num.queries_timed_out
number of queries that are dropped because they waited in the UDP socket buffer for
too long.
threadX.query.queue_time_us.max
The maximum wait time for packets in the socket buffer, in microseconds. This is
only reported when sock-queue-timeout is enabled.
threadX.num.recursivereplies
The number of replies sent to queries that needed recursive processing. Could be
smaller than threadX.num.cachemiss if due to timeouts no replies were sent for some
queries.
threadX.requestlist.avg
The average number of requests in the internal recursive processing request list on
insert of a new incoming recursive processing query.
threadX.requestlist.max
Maximum size attained by the internal recursive processing request list.
threadX.requestlist.overwritten
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.
threadX.requestlist.exceeded
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.
threadX.requestlist.current.all
Current size of the request list, includes internally generated queries (such as
priming queries and glue lookups).
threadX.requestlist.current.user
Current size of the request list, only the requests from client queries.
threadX.recursion.time.avg
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.
threadX.recursion.time.median
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 average
can be bigger than the median. This median has been calculated by interpolation
from a histogram.
threadX.tcpusage
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.
total.num.queries
summed over threads.
total.num.queries_ip_ratelimited
summed over threads.
total.num.queries_cookie_valid
summed over threads.
total.num.queries_cookie_client
summed over threads.
total.num.queries_cookie_invalid
summed over threads.
total.num.cachehits
summed over threads.
total.num.cachemiss
summed over threads.
total.num.dnscrypt.crypted
summed over threads.
total.num.dnscrypt.cert
summed over threads.
total.num.dnscrypt.cleartext
summed over threads.
total.num.dnscrypt.malformed
summed over threads.
total.num.prefetch
summed over threads.
total.num.expired
summed over threads.
total.num.queries_timed_out
summed over threads.
total.query.queue_time_us.max
the maximum of the thread values.
total.num.recursivereplies
summed over threads.
total.requestlist.avg
averaged over threads.
total.requestlist.max
the maximum of the thread requestlist.max values.
total.requestlist.overwritten
summed over threads.
total.requestlist.exceeded
summed over threads.
total.requestlist.current.all
summed over threads.
total.recursion.time.median
averaged over threads.
total.tcpusage
summed over threads.
time.now
current time in seconds since 1970.
time.up
uptime since server boot in seconds.
time.elapsed
time since last statistics printout, in seconds.
EXTENDED STATISTICS
mem.cache.rrset
Memory in bytes in use by the RRset cache.
mem.cache.message
Memory in bytes in use by the message cache.
mem.cache.dnscrypt_shared_secret
Memory in bytes in use by the dnscrypt shared secrets cache.
mem.cache.dnscrypt_nonce
Memory in bytes in use by the dnscrypt nonce cache.
mem.mod.iterator
Memory in bytes in use by the iterator module.
mem.mod.validator
Memory in bytes in use by the validator module. Includes the key cache and negative
cache.
mem.streamwait
Memory in bytes in used by the TCP and TLS stream wait buffers. These are answers
waiting to be written back to the clients.
mem.http.query_buffer
Memory in bytes used by the HTTP/2 query buffers. Containing (partial) DNS queries
waiting for request stream completion.
mem.http.response_buffer
Memory in bytes used by the HTTP/2 response buffers. Containing DNS responses
waiting to be written back to the clients.
histogram.<sec>.<usec>.to.<sec>.<usec>
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.
num.query.type.A
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 omitted for brevity.
num.query.type.other
Number of queries with query types 256-65535.
num.query.class.IN
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.
num.query.opcode.QUERY
The total number of queries over all threads with query opcode QUERY. Also printed
for other opcodes, UPDATE, ...
num.query.tcp
Number of queries that were made using TCP towards the Unbound server.
num.query.tcpout
Number of queries that the Unbound server made using TCP outgoing towards other
servers.
num.query.udpout
Number of queries that the Unbound server made using UDP outgoing towards other
servers.
num.query.tls
Number of queries that were made using TLS towards the Unbound server. These are
also counted in num.query.tcp, because TLS uses TCP.
num.query.tls.resume
Number of TLS session resumptions, these are queries over TLS towards the Unbound
server where the client negotiated a TLS session resumption key.
num.query.https
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.
num.query.ipv6
Number of queries that were made using IPv6 towards the Unbound server.
num.query.flags.RD
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.
num.query.edns.present
number of queries that had an EDNS OPT record present.
num.query.edns.DO
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.
num.query.ratelimited
The number of queries that are turned away from being send to nameserver due to
ratelimiting.
num.query.dnscrypt.shared_secret.cachemiss
The number of dnscrypt queries that did not find a shared secret in the cache.
This can be used to compute the shared secret hitrate.
num.query.dnscrypt.replay
The number of dnscrypt queries that found a nonce hit in the nonce cache and hence
are considered a query replay.
num.answer.rcode.NXDOMAIN
The number of answers to queries, from cache or from recursion, that had the return
code NXDOMAIN. Also printed for the other return codes.
num.answer.rcode.nodata
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.
num.answer.secure
Number of answers that were secure. The answer validated correctly. 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.
num.answer.bogus
Number of answers that were bogus. These answers resulted in SERVFAIL to the
client because the answer failed validation.
num.rrset.bogus
The number of rrsets marked bogus by the validator. Increased for every RRset
inspection that fails.
unwanted.queries
Number of queries that were refused or dropped because they failed the access
control settings.
unwanted.replies
Replies that were unwanted or unsolicited. Could have been random 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).
msg.cache.count
The number of items (DNS replies) in the message cache.
rrset.cache.count
The number of RRsets in the rrset cache. This includes rrsets used by the messages
in the message cache, but also delegation information.
infra.cache.count
The number of items in the infra cache. These are IP addresses with their timing
and protocol support information.
key.cache.count
The number of items in the key cache. These are DNSSEC keys, one item per
delegation point, and their validation status.
msg.cache.max_collisions
The maximum number of hash table collisions in the msg cache. This is the number of
hashes that are identical when a new element is inserted in the hash table. If the
value is very large, like hundreds, something is wrong with the performance of the
hash table, hash values are incorrect or malicious.
rrset.cache.max_collisions
The maximum number of hash table collisions in the rrset cache. This is the number
of hashes that are identical when a new element is inserted in the hash table. If
the value is very large, like hundreds, something is wrong with the performance of
the hash table, hash values are incorrect or malicious.
dnscrypt_shared_secret.cache.count
The number of items in the shared secret cache. These are precomputed 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 multiple dnscrypt queries are sent from the same client.
dnscrypt_nonce.cache.count
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` seconds.
num.query.authzone.up
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.
num.query.authzone.down
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.
num.query.aggressive.NOERROR
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.
num.query.aggressive.NXDOMAIN
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.
num.query.subnet
Number of queries that got an answer that contained EDNS client subnet data.
num.query.subnet_cache
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.
num.query.cachedb
Number of queries answered from the external cache of cachedb. These are counted
as cachemiss by the main counters, but hit the cachedb external cache after getting
processed by the cachedb module.
num.rpz.action.<rpz_action>
Number of queries answered using configured RPZ policy, per RPZ action type.
Possible actions are: nxdomain, nodata, passthru, drop, tcp-only, local-data,
disabled, and cname-override.
FILES
/etc/unbound/unbound.conf
Unbound configuration file.
/etc/unbound
directory with private keys (unbound_server.key and unbound_control.key) and
self-signed certificates (unbound_server.pem and unbound_control.pem).
SEE ALSO
unbound.conf(5), unbound(8).