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19.3.3. Example Zone File

Seen individually, directives and resource records can be difficult to grasp. However, when placed together in a single file, they become easier to understand.
The following example shows a very basic zone file.
$ORIGIN example.com.
$TTL 86400
@		IN	SOA	dns1.example.com.	hostmaster.example.com. (
			2001062501 ; serial
			21600      ; refresh after 6 hours
			3600       ; retry after 1 hour
			604800     ; expire after 1 week
			86400 )    ; minimum TTL of 1 day
;
;
		IN	NS	dns1.example.com.
		IN	NS	dns2.example.com.
dns1		IN	A	10.0.1.1
		IN	AAAA	aaaa:bbbb::1
dns2		IN	A	10.0.1.2
		IN	AAAA	aaaa:bbbb::2
;
;
@		IN	MX	10	mail.example.com.
		IN	MX	20	mail2.example.com.
mail		IN	A	10.0.1.5
		IN	AAAA	aaaa:bbbb::5
mail2		IN	A	10.0.1.6
		IN	AAAA	aaaa:bbbb::6
;
;
; This sample zone file illustrates sharing the same IP addresses
; for multiple services:
;
services	IN	A	10.0.1.10
		IN	AAAA	aaaa:bbbb::10
		IN	A	10.0.1.11
		IN	AAAA	aaaa:bbbb::11
ftp		IN	CNAME	services.example.com.
www		IN	CNAME	services.example.com.
;
;
In this example, standard directives and SOA values are used. The authoritative nameservers are set as dns1.example.com and dns2.example.com, which have A records that tie them to 10.0.1.1 and 10.0.1.2, respectively.
The email servers configured with the MX records point to mail and mail2 via A records. Since the mail and mail2 names do not end in a trailing period (.), the $ORIGIN domain is placed after them, expanding them to mail.example.com and mail2.example.com. Through the related A resource records, their IP addresses can be determined.
Services available at the standard names, such as www.example.com (WWW), are pointed at the appropriate servers using a CNAME record.
This zone file would be called into service with a zone statement in the named.conf similar to the following:
zone "example.com" IN {
	type master;
	file "example.com.zone";
	allow-update { none; };
};