BIND 8.1.2 Release Notes

New and Changed Features

New Features

Chapter 120

available because previous versions of BIND allowed multiple

CNAME records, and these records have been used in the previous

versions for load balancing.

• notify yes_or_no;

If notify is set to yes (the default), DNS NOTIFY messages are sent

when a zone, for which the server is authoritative, changes. The

NOTIFY message speeds the convergence between the master server

and its slave servers. Aslave server that receives a NOTIFY message

contacts the master server for a zone and checks if a zone transfer is

necessary. If necessary, the slave server initiates the zone transfer

immediately. You can also the NOTIFY option in the zone statement.

This overrides the options notify statement. See “Support for

DNS Change Notiﬁcation (RFC 1996)” on page 8, for more

information.

• recursion yes_or_no;

If this option is set to yes, and a DNS query requests recursion, the

server attempts to answer all the queries. If recursion is set to no,

and the server is not aware of the answer, it returns a referral

response to the client. The default value is yes. See the fetch-glue

option for more information.

Forwarding Options

You can use the forwarding facility to create a large site-wide cache on

few servers, reducing trafﬁc over links to external nameservers. You can

also use this option to allow queries by servers that intend to look up

exterior names but do not have direct access to the Internet. Forwarding

occurs only on those queries for which the server is not authoritative and

does not contain the answer in its cache.

Following are the different forwarding options:

• forwarders { [ in_addr ; [ in_addr ; ... ] ] };

This option speciﬁes the IP addresses used for forwarding. The

default value is an empty list (i.e., no forwarding).

• forward ( only | first );

This option is effective only if IP addresses are speciﬁed in the

forwarders option for forwarding. A value of first (the default

value) causes the server to ﬁrst query the IP addresses speciﬁed in