DNS/BIND resource record: PTR reverse lookup record

The PTR (pointer) record maps an IP address to a hostname and fully qualified domain name. Many applications use reverse lookups to identify the domain from which a TCP/IP connection is formed. Best practice for DNS is to create a PTR record for every A record.


To associate the host chef.tech-recipes.com. with the IP address 192.168.5.10 to the domain tech-recipes.com. in the zone file db.5.168.192 with origin 5.168.192.in-addr.arpa., use the following format:

10 IN PTR chef.tech-recipes.com.

Please note the period following the domain name in the record. This is critical beacuse it tells BIND that the domain name is attached and complete (fully qualified). Without this period, BIND will add the domain name associated with the zone file to the end of this which would make chef.tech-recipes.com.5.168.192.in-addr.arpa. which is not what we want.

Whenever you this recipe describes creating a zone file.

 

About Quinn McHenry

Quinn was one of the original co-founders of Tech-Recipes. He is currently crafting iOS applications as a senior developer at Small Planet Digital in Brooklyn, New York.
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