19.2.2. Other Statement Types
The following is a list of lesser used statement types available within
named.conf
:
-
controls
- Configures various security requirements necessary to use the
rndc
command to administer thenamed
service.Refer to Section 19.4.1, “Configuring/etc/named.conf
” to learn more about how thecontrols
statement is structured and what options are available. -
key "<key-name>"
- Defines a particular key by name. Keys are used to authenticate various actions, such as secure updates or the use of the
rndc
command. Two options are used withkey
:algorithm <algorithm-name>
— The type of algorithm used, such asdsa
orhmac-md5
.secret "<key-value>"
— The encrypted key.
Refer to Section 19.4.2, “Configuring/etc/rndc.conf
” for instructions on how to write akey
statement. -
logging
- Allows for the use of multiple types of logs, called channels. By using the
channel
option within thelogging
statement, a customized type of log can be constructed — with its own file name (file
), size limit (size
), versioning (version
), and level of importance (severity
). Once a customized channel is defined, acategory
option is used to categorize the channel and begin logging whennamed
is restarted.By default,named
logs standard messages to thesyslog
daemon, which places them in/var/log/messages
. This occurs because several standard channels are built into BIND with various severity levels, such asdefault_syslog
(which handles informational logging messages) anddefault_debug
(which specifically handles debugging messages). A default category, calleddefault
, uses the built-in channels to do normal logging without any special configuration.Customizing the logging process can be a very detailed process and is beyond the scope of this chapter. For information on creating custom BIND logs, refer to the BIND 9 Administrator Reference Manual referenced in Section 19.7.1, “Installed Documentation”. -
server
- Specifies options that affect how
named
should respond to remote nameservers, especially with regard to notifications and zone transfers.Thetransfer-format
option controls whether one resource record is sent with each message (one-answer
) or multiple resource records are sent with each message (many-answers
). Whilemany-answers
is more efficient, only newer BIND nameservers understand it. -
trusted-keys
- Contains assorted public keys used for secure DNS (DNSSEC). Refer to Section 19.5.3, “Security” for more information concerning BIND security.
-
view "<view-name>"
- Creates special views depending upon which network the host querying the nameserver is on. This allows some hosts to receive one answer regarding a zone while other hosts receive totally different information. Alternatively, certain zones may only be made available to particular trusted hosts while non-trusted hosts can only make queries for other zones.Multiple views may be used, but their names must be unique. The
match-clients
option specifies the IP addresses that apply to a particular view. Anyoptions
statement may also be used within a view, overriding the global options already configured fornamed
. Mostview
statements contain multiplezone
statements that apply to thematch-clients
list. The order in whichview
statements are listed is important, as the firstview
statement that matches a particular client's IP address is used.Refer to Section 19.5.2, “Multiple Views” for more information about theview
statement.