We will make a movie dns.

db.DOMAIN

File that maps hostnames to addresses is called db.domian. We will call ours db.movie.edu.

db.ADDR

The files mapping addresses to hostnames are called db.ADDR, where ADDR is the network number without training zeros. In our example these files will be db.192.249.249 and db.192.253.253

The db.domain and db.addr are called zone datafiles. The format of these files is called master file format.

db.cache

db.127.0.0

The db.cache and db.127.0.0 files are called overhead.

To tie all these files together you need a named.conf file.

Zone DataFiles

TTL
SOA record (start of authority for this zone)
NS record (lists a nameserver for this zone)
Other records (data about hosts in this zone)
A (name-to-address mapping)
PTR (name-to-address mapping)
CNAME (canonical name of aliases)

comments start with a semicolon.

Setting the zone default TTL

We add the following resource record to db.movie.edu file.

$TTL 3h

SOA Records

We add the following resource record to db.movie.edu file.

movie.edu. IN SOA toystory.movie.edu. al.movie.edu. (
                        1       ; Serial
                        3h      ; Refresh after 3 hours
                        1h      ; Retry after 1 hour
                        1w      ; Expire after 1 week
                        1h )    ; Negative caching TTL of 1 hour

NS Records

Here is the information about our two name servers. We add the following resource record to db.movie.edu file.

; NS Record
movie.edu.      IN NS toystory.movie.edu.
movie.edu.      IN NS wormhole.movie.edu.

Address and Alias Records

Next, we create name-to-address mappings. We add the following resource record to db.movie.edu file.

;
; Host addresses
;
localhost.movie.edu.          IN A       127.0.0.1
shrek.movie.edu.              IN A       192.249.249.2
toystory.movie.edu.           IN A       192.249.249.3
monsters-inc.movie.edu.       IN A       192.249.249.4
misery.movie.edu.             IN A       192.253.253.2
;
; Multi-homes hosts
;
wormhole.movie.edu.           IN A       192.249.249.1
wormhole.movie.edu.           IN A       192.253.253.1
;
; Aliases
;
toys.movie.edu.               IN CNAME   toystory.movie.edu.
mi.movie.edu.                 IN CNAME   monsters-inc.movie.edu.
wh.movie.edu.                 IN CNAME   wormhole.movie.edu.
wh249.movie.edu.              IN A       192.249.249.1
wh253.movie.edu.              IN A       192.253.253.1

The A stands for addresses. wormhole.movie.edu is a multihomed host. It has two addresses associated with it. CNAME is canonical name resource record. The last two entries solve a problem to check individual interface for the multihomed host.

PTR Records

Next we create address-to-name mappings. This will go in the file 192.249.249

1.249.249.192.in-addr.arpa.   IN PTR wormhole.movie.edu.
2.249.249.192.in-addr.arpa.   IN PTR shrek.movie.edu.
3.249.249.192.in-addr.arpa.   IN PTR toystory.movie.edu.
4.249.249.192.in-addr.arpa.   IN PTR monsters-inc.movie.edu.

Same data is inserted for file db.192.253.253

1.249.249.192.in-addr.arpa.   IN PTR wormhole.movie.edu.
2.249.249.192.in-addr.arpa.   IN PTR shrek.movie.edu.
3.249.249.192.in-addr.arpa.   IN PTR toystory.movie.edu.
4.249.249.192.in-addr.arpa.   IN PTR monsters-inc.movie.edu.

Complete Zone Datafiles

Here is the complete db.movie.edu:

$TTL 3h
movie.edu. IN SOA toystory.movie.edu. al.movie.edu. (
                        1       ; Serial
                        3h      ; Refresh after 3 hours
                        1h      ; Retry after 1 hour
                        1w      ; Expire after 1 week
                        1h )    ; Negative caching TTL of 1 hour
 
; NS Record
movie.edu.      IN NS toystory.movie.edu.
movie.edu.      IN NS wormhole.movie.edu.
 
;
; Host addresses
;
localhost.movie.edu.          IN A       127.0.0.1
shrek.movie.edu.              IN A       192.249.249.2
toystory.movie.edu.           IN A       192.249.249.3
monsters-inc.movie.edu.       IN A       192.249.249.4
misery.movie.edu.             IN A       192.253.253.2
;
; Multi-homes hosts
;
wormhole.movie.edu.           IN A       192.249.249.1
wormhole.movie.edu.           IN A       192.253.253.1
;
; Aliases
;
toys.movie.edu.               IN CNAME   toystory.movie.edu.
mi.movie.edu.                 IN CNAME   monsters-inc.movie.edu.
wh.movie.edu.                 IN CNAME   wormhole.movie.edu.
 
; Interface specific names
 
wh249.movie.edu.              IN A       192.249.249.1
wh253.movie.edu.              IN A       192.253.253.1

Complete PTR files

db.192.249.249

$TTL 3h
249.249.192.in-addr.arpa. IN SOA toystory.movie.edu. al.movie.edu. (
                        1       ; Serial
                        3h      ; Refresh after 3 hours
                        1h      ; Retry after 1 hour
                        1w      ; Expire after 1 week
                        1h )    ; Negative caching TTL of 1 hour

db.192.253.253

$TTL 3h
253.253.192.in-addr.arpa. IN SOA toystory.movie.edu. al.movie.edu. (
                        1       ; Serial
                        3h      ; Refresh after 3 hours
                        1h      ; Retry after 1 hour
                        1w      ; Expire after 1 week
                        1h )    ; Negative caching TTL of 1 hour

Setting up Bind

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