Bind 9 Administrator Reference Manual

Chapter 6. BIND 9 Conﬁguration Reference

6.2.14.4. Interfaces

The interfaces and ports that the server will answer queries from may be speciﬁed using the listen-on

option. listen-on takes an optional port, and an address_match_list. The server will listen on all

interfaces allowed by the address match list. If a port is not speciﬁed, port 53 will be used.

Multiple listen-on statements are allowed. For example,

listen-on { 5.6.7.8; };

listen-on port 1234 { !1.2.3.4; 1.2/16; };

will enable the nameserver on port 53 for the IP address 5.6.7.8, and on port 1234 of an address on the

machine in net 1.2 that is not 1.2.3.4.

If no listen-on is speciﬁed, the server will listen on port 53 on all interfaces.

The listen-on-v6 option is used to specify the ports on which the server will listen for incoming queries

sent using IPv6.

The server does not bind a separate socket to each IPv6 interface address as it does for IPv4. Instead, it

always listens on the IPv6 wildcard address. Therefore, the only values allowed for the

address_match_list argument to the listen-on-v6 statement are

{ any; }

and

{ none;}

Multiple listen-on-v6 options can be used to listen on multiple ports:

listen-on-v6 port 53 { any; };

listen-on-v6 port 1234 { any; };

To make the server not listen on any IPv6 address, use

listen-on-v6 { none; };

If no listen-on-v6 statement is speciﬁed, the server will not listen on any IPv6 address.

6.2.14.5. Query Address

If the server doesn’t know the answer to a question, it will query other nameservers. query-source

speciﬁes the address and port used for such queries. For queries sent over IPv6, there is a separate