12.3.3. 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.
IN MX 10 mail.example.com.
IN MX 20 mail2.example.com.
dns1 IN A 10.0.1.1
dns2 IN A 10.0.1.2
server1 IN A 10.0.1.5
server2 IN A 10.0.1.6
ftp IN A 10.0.1.3
IN A 10.0.1.4
mail IN CNAME server1
mail2 IN CNAME server2
www IN CNAME server1
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 10.0.1.2 and 10.0.1.3, respectively.
The email servers configured with the
MX records point to server1 and server2 via CNAME records. Since the server1 and server2 names do not end in a trailing period (.), the $ORIGIN domain is placed after them, expanding them to server1.example.com and server2.example.com. Through the related A resource records, their IP addresses can be determined.
FTP and Web services, available at the standard
ftp.example.com and www.example.com names, are pointed at the appropriate servers using CNAME records.
