Bind 9 Administrator Reference Manual

Chapter 6. BIND 9 Configuration Reference
$ORIGIN sets the domain name that will be appended to any unqualified records. When a zone is first
read in there is an implicit $ORIGIN <zone-name>. The current $ORIGIN is appended to the domain
specified in the $ORIGIN argument if it is not absolute.
$ORIGIN example.com.
WWW CNAME MAIN-SERVER
is equivalent to
WWW.EXAMPLE.COM. CNAME MAIN-SERVER.EXAMPLE.COM.
6.3.5.2. The $INCLUDE Directive
Syntax: $INCLUDE filename [ origin ] [ comment ]
Read and process the file filename as if it were included into the file at this point. If origin is specified
the file is processed with $ORIGIN set to that value, otherwise the current $ORIGIN is used.
The origin and the current domain name revert to the values they had prior to the $INCLUDE once the
file has been read.
Note: RFC 1035 specifies that the current origin should be restored after an $INCLUDE, but it is
silent on whether the current domain name should also be restored. BIND 9 restores both of them.
This could be construed as a deviation from RFC 1035, a feature, or both.
6.3.5.3. The $TTL Directive
Syntax: $TTL default-ttl [ comment ]
Set the default Time To Live (TTL) for subsequent records with undefined TTLs. Valid TTLs are of the
range 0-2147483647 seconds.
$TTL is defined in RFC 2308.
6.3.6. BIND Master File Extension: the $GENERATE Directive
Syntax: $GENERATE range lhs type rhs [ comment ]
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