iX 6.0)

Chapter 8 123

DNS BIND/iX

Explanation of Terms

It is also common, in fact recommended, for a DNS Server to have at

least one “backup”, another machine that will respond to queries when

the main server is down. The main server is knows as the “master” and

the backup as the “slave”. In previous versions of BIND, they were

known as “primary” and “secondary”.

The rest of this section concerns itself with only “leaf” DNS servers,

that is. servers that only serve hosts. These servers have no domains

under it, only hosts.

There are four types of db or zone ﬁles used by a DNS server, each

identiﬁed in the server’s named.conf ﬁle:

• zone.DOMAIN — provides name-to-address mapping

• zone.ADDR — provides address-to-name mapping

• zone.LOCAL — a zone.ADDR ﬁle that provides loopback mapping

• zone.CACHE — a zone.DOMAIN ﬁle that identiﬁes root name

servers; also known as the “zone.hint” ﬁle.