HardenedBSD/contrib/unbound/doc/unbound-control.8

.TH "unbound-control" "8" "Sep 27, 2016" "NLnet Labs" "unbound 1.5.10"
.\"
.\" unbound-control.8 -- unbound remote control manual
.\"
.\" Copyright (c) 2008, NLnet Labs. All rights reserved.
.\"
.\" See LICENSE for the license.
.\"
.\"
.SH "NAME"
.B unbound\-control,
.B unbound\-control\-setup
\- Unbound remote server control utility.
.SH "SYNOPSIS"
.B unbound\-control
.RB [ \-hq ]
.RB [ \-c 
.IR cfgfile ]
.RB [ \-s 
.IR server ]
.IR command
.SH "DESCRIPTION"
.B Unbound\-control
performs remote administration on the \fIunbound\fR(8) DNS server.
It reads the configuration file, contacts the unbound server over SSL
sends the command and displays the result.
.P
The available options are:
.TP
.B \-h
Show the version and commandline option help.
.TP
.B \-c \fIcfgfile
The config file to read with settings.  If not given the default
config file /var/unbound/unbound.conf is used.
.TP
.B \-s \fIserver[@port]
IPv4 or IPv6 address of the server to contact.  If not given, the
address is read from the config file.
.TP
.B \-q
quiet, if the option is given it does not print anything if it works ok.
.SH "COMMANDS"
There are several commands that the server understands.
.TP
.B start
Start the server. Simply execs \fIunbound\fR(8).  The unbound executable 
is searched for in the \fBPATH\fR set in the environment.  It is started 
with the config file specified using \fI\-c\fR or the default config file.
.TP
.B stop
Stop the server. The server daemon exits.
.TP
.B reload
Reload the server. This flushes the cache and reads the config file fresh.
.TP
.B verbosity \fInumber
Change verbosity value for logging. Same values as \fBverbosity\fR keyword in
\fIunbound.conf\fR(5).  This new setting lasts until the server is issued
a reload (taken from config file again), or the next verbosity control command.
.TP
.B 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).
.TP
.B stats
Print statistics. Resets the internal counters to zero, this can be 
controlled using the \fBstatistics\-cumulative\fR config statement. 
Statistics are printed with one [name]: [value] per line.
.TP
.B stats_noreset
Peek at statistics. Prints them like the \fBstats\fR command does, but does not
reset the internal counters to zero.
.TP
.B status
Display server status. Exit code 3 if not running (the connection to the 
port is refused), 1 on error, 0 if running.
.TP
.B local_zone \fIname\fR \fItype
Add new local zone with name and type. Like \fBlocal\-zone\fR config statement.
If the zone already exists, the type is changed to the given argument.
.TP
.B local_zone_remove \fIname
Remove the local zone with the given name.  Removes all local data inside
it.  If the zone does not exist, the command succeeds.
.TP
.B local_data \fIRR data...
Add new local data, the given resource record. Like \fBlocal\-data\fR
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.
.TP
.B local_data_remove \fIname
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.
.TP
.B 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.
.TP
.B 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.
.TP
.B lookup \fIname
Print to stdout the name servers that would be used to look up the 
name specified.
.TP
.B flush \fIname
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 
.B flush_type 
or 
.B flush_zone\fR.
.TP
.B flush_type \fIname\fR \fItype
Remove the name, type information from the cache.
.TP
.B flush_zone \fIname
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.
.TP
.B flush_bogus
Remove all bogus data from the cache.
.TP
.B 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.
.TP
.B flush_stats
Reset statistics to zero.
.TP
.B 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.
.TP
.B 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.
.TP
.B flush_infra \fIall|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.
.TP
.B dump_infra
Show the contents of the infra cache.
.TP
.B set_option \fIopt: 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.
.IP
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,
cache\-max\-ttl, cache\-min\-ttl, cache\-max\-negative\-ttl.
.TP
.B get_option \fIopt
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.
.TP
.B list_stubs
List the stub zones in use.  These are printed one by one to the output.
This includes the root hints in use.
.TP
.B list_forwards
List the forward zones in use.  These are printed zone by zone to the output.
.TP
.B list_insecure
List the zones with domain\-insecure.
.TP
.B list_local_zones
List the local zones in use.  These are printed one per line with zone type.
.TP
.B list_local_data
List the local data RRs in use.  The resource records are printed.
.TP
.B insecure_add \fIzone
Add a \fBdomain\-insecure\fR 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 \fBflush_zone\fR to remove it), does not affect the config file.
.TP
.B insecure_remove \fIzone
Removes domain\-insecure for the given zone.
.TP
.B forward_add \fR[\fI+i\fR] \fIzone addr ...
Add a new forward zone to running unbound.  With +i option also adds a
\fIdomain\-insecure\fR 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 \fIforward-zone\fR config
in unbound.conf.
.TP
.B forward_remove \fR[\fI+i\fR] \fIzone
Remove a forward zone from running unbound.  The +i also removes a
\fIdomain\-insecure\fR for the zone.
.TP
.B stub_add \fR[\fI+ip\fR] \fIzone addr ...
Add a new stub zone to running unbound.  With +i option also adds a
\fIdomain\-insecure\fR 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 \fIstub-zone\fR config in unbound.conf.
.TP
.B stub_remove \fR[\fI+i\fR] \fIzone
Remove a stub zone from running unbound.  The +i also removes a
\fIdomain\-insecure\fR for the zone.
.TP
.B forward \fR[\fIoff\fR | \fIaddr ...\fR ]
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.
.IP
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.
.IP
If \fIoff\fR 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.
.IP
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)).
.IP
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.
.TP
.B ratelimit_list \fR[\fI+a\fR]
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.
.SH "EXIT CODE"
The unbound\-control program exits with status code 1 on error, 0 on success.
.SH "SET UP"
The setup requires a self\-signed certificate and private keys for both 
the server and client.  The script \fIunbound\-control\-setup\fR 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:
.nf
    sudo \-u unbound unbound\-control\-setup
.fi
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 \fBcontrol\-enable\fR in 
\fIunbound.conf\fR.
.SH "STATISTIC COUNTERS"
The \fIstats\fR command shows a number of statistic counters.
.TP
.I threadX.num.queries
number of queries received by thread
.TP
.I threadX.num.cachehits
number of queries that were successfully answered using a cache lookup
.TP
.I threadX.num.cachemiss
number of queries that needed recursive processing
.TP
.I 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.
.TP
.I 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.
.TP
.I threadX.requestlist.avg
The average number of requests in the internal recursive processing request list on insert of a new incoming recursive processing query.
.TP
.I threadX.requestlist.max
Maximum size attained by the internal recursive processing request list.
.TP
.I 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.
.TP
.I 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.
.TP
.I threadX.requestlist.current.all
Current size of the request list, includes internally generated queries (such
as priming queries and glue lookups).
.TP
.I threadX.requestlist.current.user
Current size of the request list, only the requests from client queries.
.TP
.I 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.
.TP
.I 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.
.TP
.I 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.
.TP
.I total.num.queries
summed over threads.
.TP
.I total.num.cachehits
summed over threads.
.TP
.I total.num.cachemiss
summed over threads.
.TP
.I total.num.prefetch
summed over threads.
.TP
.I total.num.recursivereplies
summed over threads.
.TP
.I total.requestlist.avg
averaged over threads.
.TP
.I total.requestlist.max
the maximum of the thread requestlist.max values.
.TP
.I total.requestlist.overwritten
summed over threads.
.TP
.I total.requestlist.exceeded
summed over threads.
.TP
.I total.requestlist.current.all
summed over threads.
.TP
.I total.recursion.time.median
averaged over threads.
.TP
.I total.tcpusage
summed over threads.
.TP
.I time.now
current time in seconds since 1970.
.TP
.I time.up
uptime since server boot in seconds.
.TP
.I time.elapsed
time since last statistics printout, in seconds.
.SH EXTENDED STATISTICS
.TP
.I mem.total.sbrk
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.
.TP
.I mem.cache.rrset
Memory in bytes in use by the RRset cache.
.TP
.I mem.cache.message
Memory in bytes in use by the message cache.
.TP
.I mem.mod.iterator
Memory in bytes in use by the iterator module.
.TP
.I mem.mod.validator
Memory in bytes in use by the validator module. Includes the key cache and
negative cache.
.TP
.I 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.
.TP
.I 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.
.TP
.I num.query.type.other
Number of queries with query types 256\-65535.
.TP
.I 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.
.TP
.I num.query.opcode.QUERY
The total number of queries over all threads with query opcode QUERY.
Also printed for other opcodes, UPDATE, ...
.TP
.I num.query.tcp
Number of queries that were made using TCP towards the unbound server.
.TP
.I num.query.tcpout
Number of queries that the unbound server made using TCP outgoing towards
other servers.
.TP
.I num.query.ipv6
Number of queries that were made using IPv6 towards the unbound server.
.TP
.I 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.
.TP
.I num.query.edns.present
number of queries that had an EDNS OPT record present.
.TP
.I 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.
.TP
.I 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.
.TP
.I 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.
.TP
.I 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.
.TP
.I num.answer.bogus
Number of answers that were bogus.  These answers resulted in SERVFAIL
to the client because the answer failed validation.
.TP
.I num.rrset.bogus
The number of rrsets marked bogus by the validator.  Increased for every
RRset inspection that fails.
.TP
.I unwanted.queries
Number of queries that were refused or dropped because they failed the
access control settings.
.TP
.I 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).
.TP
.I msg.cache.count
The number of items (DNS replies) in the message cache.
.TP
.I 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.
.TP
.I infra.cache.count
The number of items in the infra cache.  These are IP addresses with their
timing and protocol support information.
.TP
.I key.cache.count
The number of items in the key cache.  These are DNSSEC keys, one item
per delegation point, and their validation status.
.SH "FILES"
.TP
.I /var/unbound/unbound.conf
unbound configuration file.
.TP
.I /var/unbound
directory with private keys (unbound_server.key and unbound_control.key) and
self\-signed certificates (unbound_server.pem and unbound_control.pem).
.SH "SEE ALSO"
\fIunbound.conf\fR(5), 
\fIunbound\fR(8).