rndc — name server control utility
rndc
[-b
]
[source-address
-c
]
[config-file
-k
]
[key-file
-s
]
[server
-p
]
[port
-q
]
[-r
]
[-V
]
[-y
]
[
[key_id
-4
]
| [-6
]
]
{command}
rndc controls the operation of a name server. It supersedes the ndc utility that was provided in old BIND releases. If 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.
rndc communicates with the name server over a TCP connection, sending commands authenticated with digital signatures. In the current versions of rndc and 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. This 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 key_id known to the server.
rndc reads a configuration file to determine how to contact the name server and decide what algorithm and key it should use.
Use IPv4 only.
Use IPv6 only.
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.
config-file
Use config-file
as the configuration file instead of the default,
/etc/rndc.conf
.
key-file
Use key-file
as the key file instead of the default,
/etc/rndc.key
. The key in
/etc/rndc.key
will be used to
authenticate
commands sent to the server if the config-file
does not exist.
server
server
is
the name or address of the server which matches a
server statement in the configuration file for
rndc. If no server is supplied on the
command line, the host named by the default-server clause
in the options statement of the rndc
configuration file will be used.
port
Send commands to TCP port
port
instead
of BIND 9's default control channel port, 953.
Quiet mode: Message text returned by the server will not be printed except when there is an error.
Instructs rndc to print the result code returned by named after executing the requested command (e.g., ISC_R_SUCCESS, ISC_R_FAILURE, etc).
Enable verbose logging.
key_id
Use the key key_id
from the configuration file.
key_id
must be
known by named with the same algorithm and secret string
in order for control message validation to succeed.
If no key_id
is specified, rndc will first look
for a key clause in the server statement of the server
being used, or if no server statement is present for that
host, then 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. It should therefore not have general read
or write access.
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 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 named.conf
.
The configuration is saved in a file called
(or, if named is compiled with
liblmdb, an LMDB database file called
viewname
.nzf
).
viewname
.nzdviewname
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 named is
restarted, the file will be loaded into the view
configuration, so that zones that were added
can persist after a restart.
This sample addzone command
would add the zone example.com
to the default view:
$
rndc addzone example.com '{ type master; file "example.com.db"; };'
(Note the brackets and semi-colon around the zone configuration text.)
See also rndc delzone and rndc modzone.
delzone [-clean] zone
[class
[view
]]
Delete a zone while the server is running.
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 rndc delzone command.)
If the zone was originally added via
rndc addzone, then it will be
removed permanently. However, if it was originally
configured in named.conf
, then
that original configuration is still in place; when
the server is restarted or reconfigured, the zone will
come back. To remove it permanently, it must also be
removed from named.conf
See also rndc addzone and rndc modzone.
dnstap ( -reopen | -roll [number
] )
Close and re-open DNSTAP output files.
rndc dnstap -reopen allows the output
file to be renamed externally, so
that 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.
dumpdb [-all|-cache|-zones|-adb|-bad|-fail] [view ...
]
Dump 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.)
flush
Flushes the server's cache.
flushname
name
[view
] 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.
flushtree
name
[view
] Flushes the given name, and all of its subdomains, from the view's DNS cache, address database, bad server cache, and SERVFAIL 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.
See also rndc thaw.
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 named's process id is returned.
This allows an external process to determine when named
had completed halting.
See also rndc stop.
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 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
auto-dnssec zone option
be set to maintain
,
and also requires the zone to be configured to
allow dynamic DNS.
(See "Dynamic Update Policies" in the Administrator
Reference Manual for more details.)
managed-keys (status | refresh | sync | destroy)
[class
[view
]]
Inspect and control 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, prints
the current status of the managed-keys database.
When run with the refresh
keyword,
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, forces an
immediate dump of the managed-keys database to disk
(in the file managed-keys.bind
or
(
).
This synchronizes the database with its journal file, so
that the database's current contents can be inspected
visually.
viewname
.mkeys
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 will cease until named is restarted or reconfigured, and all existing key maintenance state will be deleted.
Running rndc reconfig or restarting named immediately after this command will cause 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.
modzone zone
[class
[view
]] configuration
Modify 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 named.conf
.
If the zone was originally added via
rndc addzone, the configuration
changes will be recorded permanently and will still be
in effect after the server is restarted or reconfigured.
However, if it was originally configured in
named.conf
, then that original
configuration is still in place; when the server is
restarted or reconfigured, the zone will revert to
its original configuration. To make the changes
permanent, it must also be modified in
named.conf
See also rndc addzone and rndc delzone.
notify zone
[class
[view
]]
Resend NOTIFY messages for the zone.
notrace
Sets the server's debugging level to 0.
See also rndc trace.
nta
[( -class class
| -dump | -force | -remove | -lifetime duration
)]
domain
[view
]
Sets a DNSSEC negative trust anchor (NTA)
for domain
, with a lifetime of
duration
. The default lifetime is
configured in 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), named will abort the DNSSEC validation process and treat the data as insecure rather than bogus. This continues until the NTA's lifetime is elapsed.
NTAs persist across restarts of the named server.
The NTAs for a view are saved in a file called
,
where name
.ntaname
is the
name of the view, or if it contains characters
that are incompatible with use as a file name, a
cryptographic hash 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 will be updated to the
new value. Setting lifetime
to zero
is equivalent to -remove
.
If the -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, named will periodically
test 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 will be allowed to expire
early. The -force
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 reference a domain or view name that begins with a hyphen, use a double-hyphen on the command line to indicate the end of options.
querylog
[ on | off ] Enable or disable 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
named.conf
or by specifying
querylog yes; in the
options section of
named.conf
.
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 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 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
option.)
refresh zone
[class
[view
]]
Schedule zone maintenance for the given zone.
reload
Reload configuration file and zones.
reload zone
[class
[view
]]
Reload the given zone.
retransfer zone
[class
[view
]]
Retransfer the given slave zone from the master 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 will be regenerated with all new signatures.
scan
Scan the list of available network interfaces for changes, without performing a full reconfig or waiting for the interface-interval timer.
secroots [-] [view ...
]
Dump the security roots (i.e., trust anchors configured via trusted-keys, managed-keys, or dnssec-validation auto) and negative trust anchors for the specified views. If no view is specified, all views are dumped. Security roots will 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 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
named.conf
.
See also rndc managed-keys.
serve-stale ( on | off | reset | status ) [class
[view
]]
Enable, disable, reset, or report the current status
of the serving of stale answers as configured in
named.conf
.
If serving of stale answers is disabled by
rndc-serve-stale off, then it
will remain disabled even if named
is reloaded or reconfigured.
rndc serve-stale reset restores
the setting as configured in named.conf
.
rndc serve-stale status will report whether serving of stale answers is currently enabled, disabled by the configuration, or disabled by rndc. It will also report the values of stale-answer-ttl and max-stale-ttl.
showzone zone
[class
[view
]]
Print the configuration of a running zone.
See also rndc zonestatus.
sign zone
[class
[view
]]
Fetch 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, 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 option be set
to allow
or
maintain
,
and also requires the zone to be configured to
allow dynamic DNS.
(See "Dynamic Update Policies" in the Administrator
Reference Manual for more details.)
See also rndc loadkeys.
signing [( -list | -clear keyid/algorithm
| -clear all
| -nsec3param ( parameters
| none
) | -serial value
) ] 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. 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 will be 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 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. 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 named 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", use:
rndc signing -nsec3param 1 0 10 FFFF zone
.
To set the opt-out flag, 15 iterations, and no
salt, use:
rndc signing -nsec3param 1 1 15 - zone
.
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 will be rejected. The primary use is to set the serial on inline signed zones.
stats
Write server statistics to the statistics file. (See the statistics-file option in the BIND 9 Administrator Reference Manual.)
status
Display 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 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 named's process id is returned.
This allows an external process to determine when named
had completed stopping.
See also rndc halt.
sync [-clean] [zone
[class
[view
]]]
Sync 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.
tcp-timeouts [initial
idle
keepalive
advertised
]
When called without arguments, display the current values of the tcp-initial-timeout, tcp-idle-timeout, tcp-keepalive-timeout and tcp-advertised-timeout options. When called with arguments, update these values. This allows an administrator to make rapid adjustments when under a denial of service attack. See the descriptions of these options in the BIND 9 Administrator Reference Manual for details of their use.
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 option 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.
See also rndc freeze.
trace
Increment the servers debugging level by one.
trace level
Sets the server's debugging level to an explicit value.
See also rndc notrace.
tsig-delete
keyname
[view
]Delete a given TKEY-negotiated key from the server. (This does not apply to statically configured TSIG keys.)
tsig-list
List the names of all TSIG keys currently configured for use by named 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. By default, validation is enabled.
(Note that dnssec-enable must also be
yes
(the default value) for signatures
to be returned along with validated data. If validation is
enabled while dnssec-enable is set to
no
, the server will validate internally,
but will not supply clients with the necessary records to allow
validity to be confirmed.)
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.
See also rndc showzone.
rndc commands that specify zone names,
such as reload, retransfer
or 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 slaved 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".)