4.3. rndc --- Remote control for named(8)

4.3.1. Synopsis

rndc [-b <source-address>] [-c <config-file>] [-k <key-file>] [-s <server>] [-p <port>] [-q] [-V] [-y <key_id>] <command>

4.3.2. Description

rndc is a remote-control program that can be used to send control commands to a running named(8) process. If rndc is invoked with no arguments, it prints a short summary of the supported commands and their arguments.

rndc communicates with the named(8) process over a control channel that uses a TCP connection, on which it sends commands authenticated using HMACs (RFC 2104). A common shared secret is used by both peers to authenticate control channel messages. All commands sent over the control channel must be signed by a <key_id> known to the server.

rndc reads a configuration file to determine how to contact a specific named(8) process, and to decide what HMAC algorithm and key it should use.

4.3.3. Options

-b <source-address>

Use <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.

-c <config-file>

Use <config-file> as the rndc configuration file. The default is /etc/loop/rndc.conf.

-k <key-file>

The key in <key-file> will be used to authenticate commands sent to the server if the config-file does not exist. The default is /etc/loop/rndc.key.

-s <server>

<server> is the name or address of the server which matches a server statement in the configuration file for rndc. If no -s option is supplied, by default rndc uses the host named by the default-server clause in the options statement of the rndc configuration file.

-p <port>

Send control channel commands to the specified <port>. The default is 953.

-q

Enable quiet mode, where message text returned by the server will not be printed except when there is an error.

-V

Enable verbose logging.

-y <key_id>

Use the key identified by <key_id> from the rndc configuration file. <key_id> must be known by named(8) with the same algorithm and secret string in order for control channel message validation to succeed. If no -y option is supplied, by default rndc looks for a key clause in the server statement of the server being used, and if no server statement is present for that host, then the default-key clause of the options statement.

Warning

The rndc configuration file contains shared secrets which are used to send authenticated control channel messages to named(8) processes. It should therefore not have general read or write access.

<command>

<command> is the command that should be sent to the nameserver. See the next section for a list of commands.

4.3.4. Commands

A list of commands supported by rndc can be seen by running rndc without arguments. Currently supported commands are:

addzone <zone> [<class> [<view>]] <configuration>

Add a zone while the server is running. This command requires the allow-new-zones configuration option of named.conf(5) to be set to yes. The configuration string specified on the command line is the zone configuration text that would ordinarily be placed in named.conf(5).

The configuration is saved in a file named <hash>.nzf, where <hash> is a cryptographic hash generated from the name of the view. When named(8) is restarted, the file will be loaded into the view configuration, so that zones that were added can persist after a restart.

The following example would add the zone example.com to the default view:

$ rndc addzone example.com '{ type master; file "example.com.db"; };'

(Note the curly braces and semi-colons in the zone configuration.)

Also see the delzone command.

delzone [-clean] <zone> [<class> [<view>]]

Delete a zone while the server is running. Only zones that were originally added using the addzone command can be deleted in this manner.

If the -clean argument is specified, the zone's master file (and journal file, if any) will be deleted along with the zone. Without the -clean option, zone files must be cleaned up by hand. (If the zone is of type slave or stub, the files needing to be cleaned up will be reported in the output of the delzone command.)

Also see the addzone command.

dumpdb (-all | -cache | -zones | -adb | -bad) [<view> ...]

Dump the server's caches (default) and/or zones to the dump file for the specified views. If no view was specified, all views are dumped.

Also see the dump-file configuration option of named.conf(5).

flush

Flush the nameserver's resolver cache.

flushname <name> [<view>]

Flush the given <name> from the nameserver's resolver cache and, if applicable, from the nameserver's address database (ADB) and the bad-server cache.

flushtree <name> [<view>]

Flushes the given <name> and all of its subdomains from the nameserver's resolver cache, the address database (ADB), and the bad-server cache.

freeze [<zone> [<class> [<view>]]]

Suspend 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. It also causes changes in the journal file to be synced into the master file. All dynamic update attempts will be refused while the zone is frozen.

Also see the thaw command.

halt [-p]

Stop the server immediately. Recent changes made through dynamic update or IXFR are not saved to the master files, but will be rolled forward from the journal files when the server is restarted. If -p is specified, the named(8) process's PID is returned. This allows an external process to determine when named(8) had completed halting.

Also see the stop command.

loadkeys <zone> [<class> [<view>]]

Fetch all DNSSEC keys for the given <zone> from the key directory. If they are within their publication period, merge them into the zone's DNSKEY RRset. Unlike the sign command 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 auto-dnssec zone configuration option of named.conf(5) be set to maintain, and also requires the zone to be configured to allow dynamic updates. (See "Dynamic Update Policies" in the Loop User Manual for more details.)

Also see the sign command.

notify <zone> [<class> [<view>]]

Resend NOTIFY messages for the zone.

notrace

Sets the server's debugging level to 0.

Also see the trace command.

querylog (on | off)

Enable or disable query logging. This command can also be used without an argument to toggle query logging on and off.

Query logging can also be configured by explicitly directing the queries log category to a channel in the logging section of the named.conf(5) configuration, or by using the querylog configuration open of named.conf(5).

reconfig

Reload the configuration file and load new zones, but do not reload existing zone files even if they have changed. This is faster than a full reload command when there is a large number of zones because it avoids the need to examine the modification times of the zones files.

recursing

Dump the list of queries named(8) is currently recursing on, and the list of domains to which iterative queries are currently being sent. The second list includes the number of fetches currently active for the given domain, and how many have been passed or dropped because of the fetches-per-zone configuration option of named.conf(5).

refresh <zone> [<class> [<view>]]

Schedule zone maintenance for the given <zone>.

reload [<zone> [<class> [<view>]]]

Reload the given <zone>. If <zone> is not specified, it reloads the configuration file of named, and its zones.

retransfer <zone> [<class> [<view>]]

Retransfer the given slave <zone> from the master server.

If the <zone> is configured to use inline-signing configuration option of named.conf(5), the signed version of the zone is discarded; after the retransfer of the unsigned version is complete, the signed version will be regenerated with all new signatures.

scan

Scan the list of available network interfaces for changes, without executing a full reconfig command or waiting for the timer configured by the interface-interval configuration option of named.conf(5).

secroots [<view> ...]

Dump the server's security roots to the secroots file for the specified views. If no view is specified, security roots for all views are dumped.

sign <zone> [<class> [<view>]]

Fetch all DNSSEC keys for the given zone from the key directory (see the key-directory configuration option of named.conf(5)). If they are within their publication period, merge them 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 command requires that the auto-dnssec zone configuration option of named.conf(5) be set to allow or maintain, and also requires the zone to be configured to allow dynamic updates. (See "Dynamic Update Policies" in the Loop User Manual for more details.)

Also see the loadkeys command.

signing ( -list | -clear <keyid/algorithm> | -clear all | -nsec3param ( <parameters> | none ) )  <zone> [<class> [<view>]]

List, edit, or remove 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.

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.

signing -clear can remove a single key (specified in the same format that 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 will be retained.

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. <flags> may be set to 0 or 1, depending on whether you wish to set the opt-out bit in the NSEC3 chain. <iterations> defines the number of additional times to apply the algorithm when generating an NSEC3 hash. <salt> is a string of data expressed in hexadecimal, a hyphen (-) if no salt is to be used, or the keyword auto, which causes named(8) to generate a random 64-bit salt.

So, for example, to create an NSEC3 chain using the SHA-1 hash algorithm, no opt-out flag, 10 iterations, and a salt value of FFFF for zone example.org, use:

$ rndc signing -nsec3param 1 0 10 FFFF example.org

To set the opt-out flag, 15 iterations, and no salt, use:

$ rndc signing -nsec3param 1 1 15 - example.org

signing -nsec3param none removes an existing NSEC3 chain and replaces it with NSEC.

stats

Write server statistics to the statistics file (see the statistics-file configuration option of named.conf(5)).

status

Display status of the server. Note that the number of zones includes the internal loop/CH zone and the default ./IN hint zone if there is not an explicit root zone configured.

stop [-p]

Stop 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, the named(8) process's PID is returned. This allows an external process to determine when named(8) had completed stopping.

Also see the halt command.

sync [-clean] [<zone> [<class> [<view>]]]

Sync changes in the journal file for a dynamic zone to the master file. If the -clean argument is specified, the journal file is also removed. If no zone is specified, then all zones are synced.

thaw [<zone> [<class> [<view>]]]

Enable 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 will no longer be refused. If the zone has changed and the ixfr-from-differences configuration option of named.conf(5) is in use, then the journal file will be updated to reflect changes in the zone. Otherwise, if the zone has changed, any existing journal file will be removed.

Also see the freeze command.

trace [<level>]

Sets the nameserver's debugging level to <level>. If no <level> is specified, the current debugging level is incremented by one.

Also see the notrace command.

tsig-delete <keyname> [<view>]

Deletes a given TKEY-negotiated key from the server. (This does not apply to statically configured TSIG keys.)

tsig-list

Lists the names of all TSIG keys currently configured for use by named(8) in each view. The list includes both statically configured keys and dynamic TKEY-negotiated keys.

validation ( on | off | status ) [<view> ...]

Enable, disable, or check the current status of DNSSEC validation. dnssec-enable configuration option of named.conf(5) also needs to be set to yes or auto for this command to be effective. It defaults to on.

zonestatus <zone> [<class> [<view>]]

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.

4.3.5. Files

/etc/loop/rndc.conf

The default configuration file for rndc. A complete description of the configuration file is provided in rndc.conf(5).

/etc/loop/rndc.key

The default key used to authenticate commands sent to the server if the configuration file does not exist.

4.3.6. See also

rndc.conf(5), rndc-confgen(1), named(8), named.conf(5)