Chapter 16. Berkeley Internet Name Domain (BIND)

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allow recursion

  Similar to

allow query

, except it applies to recursive queries. By de 

fault, all hosts are allowed to perform recursive queries on the nameserver.

directory

  Changes the

named

working directory to something other than the default,

/var/named

.

forward

  Controls how forwarding occurs, if the

forwarders

option contains valid IP ad 

dresses designating where to send requests.

If the

first

option is used, then the nameservers specified in the

forwarders

option are queried

first for the information, and if they do not have it,

named

will attempt the resolution itself.

If the

only

option is used,

named

will not attempt the resolution itself if the forwarders are not

successful.

forwarders

  Specifies a list of nameservers where requests should be forwarded for resolu 

tion.

listen on

  Specifies the network interface that

named

will use to listen for queries. By

default, all interfaces are used.

This option is useful if you have more than one network interface and would like to limit the

systems that can make requests of your nameserver. For example, if you have a machine serving

as a gateway and a nameserver, and you would like to block any requests except those that

originate from your private network, your

listen on

option might look like this:

options {

listen on { 10.0.1.1; };

};

In this way, only requests that arrive from the network interface serving the private network

(

10.0.1.1

) will be accepted.

notify

  Controls whether

named

notifies the slave servers when a zone is updated. The default

is

yes

, but you can set this to

no

, to prevent slaves from being notified, or

explicit

, to only

notify servers in an

also notify

list.

pid file

  Allows you to specify the location of the process ID file created by

named

when

it starts.

statistics file

  Allows you to specify the location of where the statistics file is written.

By default,

named

statistics are saved in

/var/named/named.stats

.

Dozens of other options are also available, many of which rely upon one another to work properly.

See the BIND 9 Administrator Reference Manual for more details.

  server

  Defines particular options that affect how

named

should act toward remote nameservers,

especially regarding notifications and zone transfers.

The

transfer 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

). While

many answers

is more efficient, only newer BIND nameservers understand it.

  trusted keys

  Contains assorted public keys used for DNSSEC. See Section 16.4.3 for an

introduction to BIND security.

  view " view name "

  Creates special views that respond with a particular type of informa 

A

tion depending upon the host contacting the nameserver. This allows some hosts to receive one

answer regarding a particular zone while other hosts receive totally different information. Alterna 

tively, 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, so long as their names are unique. The

match clients

option spec 

ifies the IP addresses that apply to a particular view. Any

option

statements may also be used

within a view, overriding the global options already configured for

named

. Most

view

statements

contain multiple

zone

statements that apply to the

match clients

list. The order in which

view