238

Chapter 16. Berkeley Internet Name Domain (BIND)

Seconds

Other Time Units

60

1M

1800

30M

3600

1H

10800

3H

21600

6H

43200

12H

86400

1D

259200

3D

604800

1W

Table 16 1. Seconds compared to other time units

The following example illustrates the form an

SOA

resource record might take when it is configured

with real values.

@

IN

SOA

dns1.domain.com.

hostmaster.domain.com. (

2001062501 ; serial

21600

; refresh after 6 hours

3600

; retry after 1 hour

604800

; expire after 1 week

86400 )

; minimum TTL of 1 day

16.2.2.3. Zone File Examples

Seen individually, the directives and resource records can be difficult to grasp. However, everything

makes much more sense when it is placed together in a common file. The next example shows a very

basic zone file.

$ORIGIN domain.com

$TTL 86400

@

IN

SOA

dns1.domain.com.

hostmaster.domain.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.domain.com.

IN

NS

dns2.domain.com.

IN

MX

10

mail.domain.com.

IN

MX

20

mail2.domain.com.

IN

A

10.0.1.5

server1

IN

A

10.0.1.5

server2

IN

A

10.0.1.7

dns1

IN

A

10.0.1.2

dns2

IN

A

10.0.1.3

ftp

IN

CNAME

server1

mail

IN

CNAME

server1

mail2

IN

CNAME

server2

www

IN

CNAME

server2