The hosts.rev File

The hosts.rev file specifies a zone in the in-addr.arpa. domain, the special domain that allows reverse (address-to-name) mapping. The name of this file is specified in the boot file.

Setting Up the hosts.rev File

The hosts.rev file sets up inverse mapping.

The name hosts.rev is a generic name indicating the file's purpose and content. If you have more than one zone, each zone must have its own hosts.rev file and each of these zone hosts.rev files must have a unique name. For example, if your DNS domain is divided into doc.com and sales.doc.com zones, you could name one hosts.rev file doc.rev and the other sales.rev.

Example 5–17 Sample hosts.rev File

; SOA rec
6.45.123.in-addr.arpa.  IN SOA sirius.doc.com. sysop.centauri.doc.com. (
                 1997071401       ;  serial number (YYYYMMDD##)
                      10800       ;  refresh every 3 hours
                      10800       ;  retry every 3 hours
                      604800      ;  expire after a week
                      86400 )     ;  TTL of 1 day
; Name Servers
6.45.123.in-addr.arpa.   IN  NS  sirius.doc.com.
1                        IN  PTR sirius.doc.com.

A hosts.rev file contains these elements:

• A Start of Authority (SOA) record

• One or more Name Server (NS) records identifying master and slave DNS name servers. Server names should be fully qualified.

• A PTR record for each host in the zone. Machine names should be fully qualified.

(SeeResource Record Types for detailed descriptions of these resource record types.)