BACK and named.192.168.1

This page contains the master zone file for the fictional domain and its reverse address lookup file. 

In the file after the header part of the file the computer hostnames are on the left side of the file (mars, earth, mercury and are all computer names, the name must either contain the domain name in the host name or it must have no no trailing period after the computer name, -the domain name will be appended to the domain if the period is left off.) Next is the IN which specifies that the address is and Internet address.  The A is for Address, MX is for mail server, and CNAME is a common name for a computer that already has a listed name.  The last item going across is the computers IP address -in the case of an MX or CNAME entry you may use the hostname instead of the IP address as the server will lookup the name.

// file

@           IN SOA    (
                                  IN NS
                                  IN A

mars                          IN A
                                  IN MX   100
earth                         IN A
mercury                    IN A
                                  IN MX   100       IN A
ftp.mars                    IN A                   IN CNAME
www.mars                 IN A
www.mercury           IN A
earth2                       IN A
mars2                       IN A        l92.168.1.66
localhost                   IN A

The named.192.168.1 file holds the information the server needs to reverse the IP address to get the hostname.  In this file after the header part the fourth octet of the IP address is put on the left and the IN is followed by a PTR (domain name pointer).  The last item for each record is the full hostname with the domain added on to it -note the trailing period, it is necessary so the server doesn't try to append the domain name onto the end of it.

// Reverse IP address to hostname lookup file for domain


@                 IN SOA (

@                 IN NS
38                IN PTR
67                IN PTR
35                IN PTR
66                IN PTR
68                IN PTR