.. Copyright (C) Internet Systems Consortium, Inc. ("ISC") .. .. SPDX-License-Identifier: MPL-2.0 .. .. This Source Code Form is subject to the terms of the Mozilla Public .. License, v. 2.0. If a copy of the MPL was not distributed with this .. file, you can obtain one at https://mozilla.org/MPL/2.0/. .. .. See the COPYRIGHT file distributed with this work for additional .. information regarding copyright ownership. .. highlight: console .. iscman:: rndc .. program:: rndc .. _man_rndc: rndc - name server control utility ---------------------------------- Synopsis ~~~~~~~~ :program:`rndc` [**-b** source-address] [**-c** config-file] [**-k** key-file] [**-s** server] [**-p** port] [**-q**] [**-r**] [**-V**] [**-y** server_key] [[**-4**] | [**-6**]] {command} Description ~~~~~~~~~~~ :program:`rndc` controls the operation of a name server. If :program:`rndc` is invoked with no command line options or arguments, it prints a short summary of the supported commands and the available options and their arguments. :program:`rndc` communicates with the name server over a TCP connection, sending commands authenticated with digital signatures. In the current versions of :program:`rndc` and :iscman:`named`, the only supported authentication algorithms are HMAC-MD5 (for compatibility), HMAC-SHA1, HMAC-SHA224, HMAC-SHA256 (default), HMAC-SHA384, and HMAC-SHA512. They use a shared secret on each end of the connection, which provides TSIG-style authentication for the command request and the name server's response. All commands sent over the channel must be signed by a server_key known to the server. :program:`rndc` reads a configuration file to determine how to contact the name server and decide what algorithm and key it should use. Options ~~~~~~~ .. option:: -4 This option indicates use of IPv4 only. .. option:: -6 This option indicates use of IPv6 only. .. option:: -b source-address This option indicates ``source-address`` as the source address for the connection to the server. Multiple instances are permitted, to allow setting of both the IPv4 and IPv6 source addresses. .. option:: -c config-file This option indicates ``config-file`` as the configuration file instead of the default, |rndc_conf|. .. option:: -k key-file This option indicates ``key-file`` as the key file instead of the default, |rndc_key|. The key in |rndc_key| is used to authenticate commands sent to the server if the config-file does not exist. .. option:: -s server ``server`` is the name or address of the server which matches a server statement in the configuration file for :program:`rndc`. If no server is supplied on the command line, the host named by the default-server clause in the options statement of the :program:`rndc` configuration file is used. .. option:: -p port This option instructs BIND 9 to send commands to TCP port ``port`` instead of its default control channel port, 953. .. option:: -q This option sets quiet mode, where message text returned by the server is not printed unless there is an error. .. option:: -r This option instructs :program:`rndc` to print the result code returned by :iscman:`named` after executing the requested command (e.g., ISC_R_SUCCESS, ISC_R_FAILURE, etc.). .. option:: -t timeout This option sets the idle timeout period for :program:`rndc` to ``timeout`` seconds. The default is 60 seconds, and the maximum settable value is 86400 seconds (1 day). If set to 0, there is no timeout. .. option:: -V This option enables verbose logging. .. option:: -y server_key This option indicates use of the key ``server_key`` from the configuration file. For control message validation to succeed, ``server_key`` must be known by :iscman:`named` with the same algorithm and secret string. If no ``server_key`` is specified, :program:`rndc` first looks for a key clause in the server statement of the server being used, or if no server statement is present for that host, then in the default-key clause of the options statement. Note that the configuration file contains shared secrets which are used to send authenticated control commands to name servers, and should therefore not have general read or write access. Commands ~~~~~~~~ A list of commands supported by :program:`rndc` can be seen by running :program:`rndc` without arguments. Currently supported commands are: .. option:: addzone zone [class [view]] configuration This command adds a zone while the server is running. This command requires the ``allow-new-zones`` option to be set to ``yes``. The configuration string specified on the command line is the zone configuration text that would ordinarily be placed in :iscman:`named.conf`. The configuration is saved in a file called ``viewname.nzf`` (or, if :iscman:`named` is compiled with liblmdb, an LMDB database file called ``viewname.nzd``). ``viewname`` is the name of the view, unless the view name contains characters that are incompatible with use as a file name, in which case a cryptographic hash of the view name is used instead. When :iscman:`named` is restarted, the file is loaded into the view configuration so that zones that were added can persist after a restart. This sample ``addzone`` command adds the zone ``example.com`` to the default view: ``rndc addzone example.com '{ type primary; file "example.com.db"; };'`` (Note the brackets around and semi-colon after the zone configuration text.) See also :option:`rndc delzone` and :option:`rndc modzone`. .. option:: delzone [-clean] zone [class [view]] This command deletes a zone while the server is running. If the ``-clean`` argument is specified, the zone's master file (and journal file, if any) are deleted along with the zone. Without the ``-clean`` option, zone files must be deleted manually. (If the zone is of type ``secondary`` or ``stub``, the files needing to be removed are reported in the output of the ``rndc delzone`` command.) If the zone was originally added via ``rndc addzone``, then it is removed permanently. However, if it was originally configured in :iscman:`named.conf`, then that original configuration remains in place; when the server is restarted or reconfigured, the zone is recreated. To remove it permanently, it must also be removed from :iscman:`named.conf`. See also :option:`rndc addzone` and :option:`rndc modzone`. .. option:: dnssec The following commands allow you to interact with the "dnssec-policy" of a given zone. .. program:: rndc dnssec .. option:: -checkds [-key id [-alg algorithm]] [-when time] (published | withdrawn) zone [class [view]] This command informs :iscman:`named` that the DS for a specified zone's key-signing key (KSK) has been confirmed to be published in, or withdrawn from, the parent zone. This is required in order to complete a KSK rollover. The ``-key id`` and ``-alg algorithm`` arguments can be used to specify a particular KSK, if necessary; if there is only one key acting as a KSK for the zone, these arguments can be omitted. The time of publication or withdrawal for the DS is set to the current time by default, but can be overridden to a specific time with the argument ``-when time``, where ``time`` is expressed in YYYYMMDDHHMMSS notation. .. program:: rndc dnssec .. option:: -rollover -key id [-alg algorithm] [-when time] zone [class [view]] This command allows you to schedule key rollover for a specific key (overriding the original key lifetime). The ``-key id`` and ``-alg algorithm`` arguments specify which key to roll. The time to start the rollover can be set with ``-when time``, where ``time`` is expressed in YYYYMMDDHHMMSS. If not set the rollover will start immediately. .. program:: rndc dnssec .. option:: -status [-v] zone [class [view]] This command shows the DNSSEC signing state for the specified zone. Adding ``-v`` also lists no longer used keys and shows the key states of the keys. .. program:: rndc dnssec .. option:: -step zone [class [view]] This command sends a signal to an instance of :iscman:`named` for a zone configured with ``dnssec-policy`` in manual mode, telling it to continue with the operations that had previously been blocked but logged. This gives the human operator a chance to review the log messages, understand what will happen next and then, using ``rndc dnssec -step``, to inform :iscman:`named` to proceed to the next stage. .. program:: rndc .. option:: dnstap (-reopen | -roll [number]) This command closes and re-opens DNSTAP output files. ``rndc dnstap -reopen`` allows the output file to be renamed externally, so that :iscman:`named` can truncate and re-open it. ``rndc dnstap -roll`` causes the output file to be rolled automatically, similar to log files. The most recent output file has ".0" appended to its name; the previous most recent output file is moved to ".1", and so on. If ``number`` is specified, then the number of backup log files is limited to that number. .. option:: dumpdb [-all | -cache | -zones | -adb | -bad | -expired | -fail] [view ...] This command dumps the server's caches (default) and/or zones to the dump file for the specified views. If no view is specified, all views are dumped. (See the ``dump-file`` option in the BIND 9 Administrator Reference Manual.) .. option:: fetchlimit [view] This command dumps a list of servers that are currently being rate-limited as a result of ``fetches-per-server`` settings, and a list of domain names that are currently being rate-limited as a result of ``fetches-per-zone`` settings. .. option:: flush This command flushes the server's cache. .. option:: flushname name [view] This command flushes the given name from the view's DNS cache and, if applicable, from the view's nameserver address database, bad server cache, and SERVFAIL cache. .. option:: flushtree name [view] This command flushes the given name, and all of its subdomains, from the view's DNS cache, address database, bad server cache, and SERVFAIL cache. .. option:: freeze [zone [class [view]]] This command suspends updates to a dynamic zone. If no zone is specified, then all zones are suspended. This allows manual edits to be made to a zone normally updated by dynamic update, and causes changes in the journal file to be synced into the master file. All dynamic update attempts are refused while the zone is frozen. See also :option:`rndc thaw`. .. option:: halt [-p] This command stops the server immediately. Recent changes made through dynamic update or IXFR are not saved to the master files, but are rolled forward from the journal files when the server is restarted. If ``-p`` is specified, :iscman:`named`'s process ID is returned. This allows an external process to determine when :iscman:`named` has completed halting. See also :option:`rndc stop`. .. option:: skr -import file zone [class [view]] This command allows you to import a SKR file for the specified zone, to support offline KSK signing. .. option:: loadkeys [zone [class [view]]] This command fetches all DNSSEC keys for the given zone from the key directory. If they are within their publication period, they are merged into the zone's DNSKEY RRset. Unlike :option:`rndc sign`, however, the zone is not immediately re-signed by the new keys, but is allowed to incrementally re-sign over time. This command requires that the zone be configured with a ``dnssec-policy``. .. option:: managed-keys (status | refresh | sync | destroy) [class [view]] This command inspects and controls the "managed-keys" database which handles :rfc:`5011` DNSSEC trust anchor maintenance. If a view is specified, these commands are applied to that view; otherwise, they are applied to all views. - When run with the ``status`` keyword, this prints the current status of the managed-keys database. - When run with the ``refresh`` keyword, this forces an immediate refresh query to be sent for all the managed keys, updating the managed-keys database if any new keys are found, without waiting the normal refresh interval. - When run with the ``sync`` keyword, this forces an immediate dump of the managed-keys database to disk (in the file ``managed-keys.bind`` or (``viewname.mkeys``). This synchronizes the database with its journal file, so that the database's current contents can be inspected visually. - When run with the ``destroy`` keyword, the managed-keys database is shut down and deleted, and all key maintenance is terminated. This command should be used only with extreme caution. Existing keys that are already trusted are not deleted from memory; DNSSEC validation can continue after this command is used. However, key maintenance operations cease until :iscman:`named` is restarted or reconfigured, and all existing key maintenance states are deleted. Running :option:`rndc reconfig` or restarting :iscman:`named` immediately after this command causes key maintenance to be reinitialized from scratch, just as if the server were being started for the first time. This is primarily intended for testing, but it may also be used, for example, to jumpstart the acquisition of new keys in the event of a trust anchor rollover, or as a brute-force repair for key maintenance problems. .. option:: memprof [(on | off | dump)] This command controls memory profiling. To have any effect, :iscman:`named` must be built with jemalloc, the library have profiling support enabled and run with the ``prof:true`` allocator configuration. (either via ``MALLOC_CONF`` or ``/etc/malloc.conf``) The ``prof_active:false`` option is recommended to ensure the profiling overhead does not affect :iscman:`named` when not needed. The ``on`` and ``off`` options will start and stop the jemalloc memory profiling respectively. When run with the `dump` option, :iscman:`named` will dump the profile to the working directory. The name will be chosen automatically by jemalloc. .. option:: modzone zone [class [view]] configuration This command modifies the configuration of a zone while the server is running. This command requires the ``allow-new-zones`` option to be set to ``yes``. As with ``addzone``, the configuration string specified on the command line is the zone configuration text that would ordinarily be placed in :iscman:`named.conf`. If the zone was originally added via :option:`rndc addzone`, the configuration changes are recorded permanently and are still in effect after the server is restarted or reconfigured. However, if it was originally configured in :iscman:`named.conf`, then that original configuration remains in place; when the server is restarted or reconfigured, the zone reverts to its original configuration. To make the changes permanent, it must also be modified in :iscman:`named.conf`. See also :option:`rndc addzone` and :option:`rndc delzone`. .. option:: notify zone [class [view]] This command resends NOTIFY messages for the zone. .. option:: notrace This command sets the server's debugging level to 0. See also :option:`rndc trace`. .. option:: nta [(-class class | -dump | -force | -remove | -lifetime duration)] domain [view] This command sets a DNSSEC negative trust anchor (NTA) for ``domain``, with a lifetime of ``duration``. The default lifetime is configured in :iscman:`named.conf` via the ``nta-lifetime`` option, and defaults to one hour. The lifetime cannot exceed one week. A negative trust anchor selectively disables DNSSEC validation for zones that are known to be failing because of misconfiguration rather than an attack. When data to be validated is at or below an active NTA (and above any other configured trust anchors), :iscman:`named` aborts the DNSSEC validation process and treats the data as insecure rather than bogus. This continues until the NTA's lifetime has elapsed. NTAs persist across restarts of the :iscman:`named` server. The NTAs for a view are saved in a file called ``name.nta``, where ``name`` is the name of the view; if it contains characters that are incompatible with use as a file name, a cryptographic hash is generated from the name of the view. An existing NTA can be removed by using the ``-remove`` option. An NTA's lifetime can be specified with the ``-lifetime`` option. TTL-style suffixes can be used to specify the lifetime in seconds, minutes, or hours. If the specified NTA already exists, its lifetime is updated to the new value. Setting ``lifetime`` to zero is equivalent to ``-remove``. If ``-dump`` is used, any other arguments are ignored and a list of existing NTAs is printed. Note that this may include NTAs that are expired but have not yet been cleaned up. Normally, :iscman:`named` periodically tests to see whether data below an NTA can now be validated (see the ``nta-recheck`` option in the Administrator Reference Manual for details). If data can be validated, then the NTA is regarded as no longer necessary and is allowed to expire early. The ``-force`` parameter overrides this behavior and forces an NTA to persist for its entire lifetime, regardless of whether data could be validated if the NTA were not present. The view class can be specified with ``-class``. The default is class ``IN``, which is the only class for which DNSSEC is currently supported. All of these options can be shortened, i.e., to ``-l``, ``-r``, ``-d``, ``-f``, and ``-c``. Unrecognized options are treated as errors. To refer to a domain or view name that begins with a hyphen, use a double-hyphen (--) on the command line to indicate the end of options. .. option:: querylog [(on | off)] This command enables or disables query logging. For backward compatibility, this command can also be used without an argument to toggle query logging on and off. Query logging can also be enabled by explicitly directing the ``queries`` ``category`` to a ``channel`` in the ``logging`` section of :iscman:`named.conf`, or by specifying ``querylog yes;`` in the ``options`` section of :iscman:`named.conf`. .. option:: reconfig This command reloads the configuration file and loads new zones, but does not reload existing zone files even if they have changed. This is faster than a full :option:`rndc reload` when there is a large number of zones, because it avoids the need to examine the modification times of the zone files. .. option:: recursing This command dumps the list of queries :iscman:`named` is currently recursing on, and the list of domains to which iterative queries are currently being sent. The first list includes all unique clients that are waiting for recursion to complete, including the query that is awaiting a response and the timestamp (seconds since the Unix epoch) of when named started processing this client query. The second list comprises of domains for which there are active (or recently active) fetches in progress. It reports the number of active fetches for each domain and the number of queries that have been passed (allowed) or dropped (spilled) as a result of the ``fetches-per-zone`` limit. (Note: these counters are not cumulative over time; whenever the number of active fetches for a domain drops to zero, the counter for that domain is deleted, and the next time a fetch is sent to that domain, it is recreated with the counters set to zero). .. option:: refresh zone [class [view]] This command schedules zone maintenance for the given zone. .. option:: reload This command reloads the configuration file and zones. .. program:: rndc reload .. option:: zone [class [view]] If a zone is specified, this command reloads only the given zone. If no zone is specified, the reloading happens asynchronously. .. program:: rndc .. option:: reset-stats This command resets the requested statistics counters. At least one counter name must be provided. Currently the following counters are supported: ``recursive-high-water``, ``tcp-high-water``. .. option:: responselog [on | off] This command enables or disables response logging. For backward compatibility, this command can also be used without an argument to toggle response logging on and off. Unlike query logging, response logging cannot be enabled by explicitly directing the ``responses`` ``category`` to a ``channel`` in the ``logging`` section of :iscman:`named.conf`, but it can still be enabled by specifying ``responselog yes;`` in the ``options`` section of :iscman:`named.conf`. .. option:: retransfer [-force] zone [class [view]] This command retransfers the given secondary zone from the primary server. If the zone is configured to use ``inline-signing``, the signed version of the zone is discarded; after the retransfer of the unsigned version is complete, the signed version is regenerated with new signatures. With the optional ``-force`` argument provided if there is an ongoing zone transfer it will be aborted before a new zone transfer is scheduled. .. option:: scan This command scans the list of available network interfaces for changes, without performing a full :option:`rndc reconfig` or waiting for the ``interface-interval`` timer. .. option:: secroots [-] [view ...] This command dumps the security roots (i.e., trust anchors configured via ``trust-anchors``, or the ``managed-keys`` or ``trusted-keys`` statements [both deprecated], or ``dnssec-validation auto``) and negative trust anchors for the specified views. If no view is specified, all views are dumped. Security roots indicate whether they are configured as trusted keys, managed keys, or initializing managed keys (managed keys that have not yet been updated by a successful key refresh query). If the first argument is ``-``, then the output is returned via the :program:`rndc` response channel and printed to the standard output. Otherwise, it is written to the secroots dump file, which defaults to ``named.secroots``, but can be overridden via the ``secroots-file`` option in :iscman:`named.conf`. See also :option:`rndc managed-keys`. .. option:: serve-stale (on | off | reset | status) [class [view]] This command enables, disables, resets, or reports the current status of the serving of stale answers as configured in :iscman:`named.conf`. If serving of stale answers is disabled by ``rndc-serve-stale off``, then it remains disabled even if :iscman:`named` is reloaded or reconfigured. ``rndc serve-stale reset`` restores the setting as configured in :iscman:`named.conf`. ``rndc serve-stale status`` reports whether caching and serving of stale answers is currently enabled or disabled. It also reports the values of ``stale-answer-ttl`` and ``max-stale-ttl``. .. option:: showzone zone [class [view]] If the server is configured with ``allow-new-zones`` set to ``yes``, then this command prints the configuration of a running zone. See also :option:`rndc addzone`, :option:`rndc modzone`. and :option:`rndc delzone`. .. option:: sign zone [class [view]] This command fetches all DNSSEC keys for the given zone from the key directory (see the ``key-directory`` option in the BIND 9 Administrator Reference Manual). If they are within their publication period, they are merged into the zone's DNSKEY RRset. If the DNSKEY RRset is changed, then the zone is automatically re-signed with the new key set. This will replace signatures of inactive keys with signatures from active keys, and update signatures that expire within the refresh interval. This command requires that the zone be configured with a ``dnssec-policy``. See also :option:`rndc loadkeys`. .. option:: signing [(-list | -clear keyid/algorithm | -clear all | -nsec3param (parameters | none) | -serial value) zone [class [view]] This command lists, edits, or removes the DNSSEC signing-state records for the specified zone. The status of ongoing DNSSEC operations, such as signing or generating NSEC3 chains, is stored in the zone in the form of DNS resource records of type ``sig-signing-type``. ``rndc signing -list`` converts these records into a human-readable form, indicating which keys are currently signing or have finished signing the zone, and which NSEC3 chains are being created or removed. ``rndc signing -clear`` can remove a single key (specified in the same format that ``rndc signing -list`` uses to display it), or all keys. In either case, only completed keys are removed; any record indicating that a key has not yet finished signing the zone is retained. ``rndc signing -nsec3param`` sets the NSEC3 parameters for a zone. This is the only supported mechanism for using NSEC3 with ``inline-signing`` zones. Parameters are specified in the same format as an NSEC3PARAM resource record: ``hash algorithm``, ``flags``, ``iterations``, and ``salt``, in that order. Currently, the only defined value for ``hash algorithm`` is ``1``, representing SHA-1. The ``flags`` may be set to ``0`` or ``1``, depending on whether the opt-out bit in the NSEC3 chain should be set. ``iterations`` defines the number of additional times to apply the algorithm when generating an NSEC3 hash. The ``salt`` is a string of data expressed in hexadecimal, a hyphen (``-``) if no salt is to be used, or the keyword ``auto``, which causes :iscman:`named` to generate a random 64-bit salt. The only recommended configuration is ``rndc signing -nsec3param 1 0 0 - zone``, i.e. no salt, no additional iterations, no opt-out. .. warning:: Do not use extra iterations, salt, or opt-out unless all their implications are fully understood. A higher number of iterations causes interoperability problems and opens servers to CPU-exhausting DoS attacks. ``rndc signing -nsec3param none`` removes an existing NSEC3 chain and replaces it with NSEC. ``rndc signing -serial value`` sets the serial number of the zone to ``value``. If the value would cause the serial number to go backwards, it is rejected. The primary use of this parameter is to set the serial number on inline signed zones. .. option:: stats This command writes server statistics to the statistics file. (See the ``statistics-file`` option in the BIND 9 Administrator Reference Manual.) .. option:: status This command displays the status of the server. Note that the number of zones includes the internal ``bind/CH`` zone and the default ``./IN`` hint zone, if there is no explicit root zone configured. .. option:: stop -p This command stops the server, making sure any recent changes made through dynamic update or IXFR are first saved to the master files of the updated zones. If ``-p`` is specified, :iscman:`named`'s process ID is returned. This allows an external process to determine when :iscman:`named` has completed stopping. See also :option:`rndc halt`. .. option:: sync -clean [zone [class [view]]] This command syncs changes in the journal file for a dynamic zone to the master file. If the "-clean" option is specified, the journal file is also removed. If no zone is specified, then all zones are synced. .. option:: tcp-timeouts [initial idle keepalive advertised] When called without arguments, this command displays the current values of the ``tcp-initial-timeout``, ``tcp-idle-timeout``, ``tcp-keepalive-timeout``, and ``tcp-advertised-timeout`` options. When called with arguments, these values are updated. This allows an administrator to make rapid adjustments when under a denial-of-service (DoS) attack. See the descriptions of these options in the BIND 9 Administrator Reference Manual for details of their use. .. option:: thaw [zone [class [view]]] This command enables updates to a frozen dynamic zone. If no zone is specified, then all frozen zones are enabled. This causes the server to reload the zone from disk, and re-enables dynamic updates after the load has completed. After a zone is thawed, dynamic updates are no longer refused. If the zone has changed and the ``ixfr-from-differences`` option is in use, the journal file is updated to reflect changes in the zone. Otherwise, if the zone has changed, any existing journal file is removed. If no zone is specified, the reloading happens asynchronously. See also :option:`rndc freeze`. .. option:: trace [level] If no level is specified, this command increments the server's debugging level by one. .. program:: rndc trace .. option:: level If specified, this command sets the server's debugging level to the provided value. See also :option:`rndc notrace`. .. program:: rndc .. option:: validation (on | off | status) [view ...] This command enables, disables, or checks the current status of DNSSEC validation. By default, validation is enabled. The cache is flushed when validation is turned on or off to avoid using data that might differ between states. .. option:: zonestatus zone [class [view]] This command displays the current status of the given zone, including the master file name and any include files from which it was loaded, when it was most recently loaded, the current serial number, the number of nodes, whether the zone supports dynamic updates, whether the zone is DNSSEC signed, whether it uses automatic DNSSEC key management or inline signing, and the scheduled refresh or expiry times for the zone. See also :option:`rndc showzone`. :program:`rndc` commands that specify zone names, such as :option:`reload` :option:`retransfer`, or :option:`zonestatus`, can be ambiguous when applied to zones of type ``redirect``. Redirect zones are always called ``.``, and can be confused with zones of type ``hint`` or with secondary copies of the root zone. To specify a redirect zone, use the special zone name ``-redirect``, without a trailing period. (With a trailing period, this would specify a zone called "-redirect".) Limitations ~~~~~~~~~~~ There is currently no way to provide the shared secret for a ``server_key`` without using the configuration file. Several error messages could be clearer. See Also ~~~~~~~~ :iscman:`rndc.conf(5) `, :iscman:`rndc-confgen(8) `, :iscman:`named(8) `, :iscman:`named.conf(5) `, BIND 9 Administrator Reference Manual.