DOMAIN Cache File Format for TCP/IP

Purpose

Defines the root name server or servers for a DOMAIN name server host.

Description

The cache file is one of the DOMAIN data files and contains the addresses of the servers that are authoritative name servers for the root domain of the network. The name of this file is defined in the named boot file. If the host serves more than one domain, the cache file should contain an entry for the authoritative name server for each domain.

All entries in this file must be in Standard Resource Record Format. Valid resource records in this file are:

• Name Server (NS)
• Address (A)

Except for comments (starting with a ; [semicolon] and continuing to the end of the line), the resource records in the data files generally follow the format of the resource records that the named daemon returns in response to queries from resolver routines.

Examples

The following examples show the various ways to use the cache data file. This example is valid for any name server or either of the two networks.

Network abc consists of:

• gobi.abc, the primary name server for the abc network, 192.9.201.2
• mojave.abc, a host machine, 192.9.201.6
• sandy.abc, secondary name server for the abc network and gateway between abc and xyz, 192.9.201.3

Network xyz consists of:

• kalahari.xyz, primary name server for the xyz network, 160.9.201.4
• lopnor.xyz, a host machine, 160.9.201.5
• sahara.xyz, a host machine and cache-only name server for the xyz network, 160.9.201.13
• sandy.xyz, a secondary name server for the xyz network and gateway between abc and xyz, 160.9.201.3
  Note: sandy, a gateway host, is on both networks and also serves as secondary name server for both.

The following are sample entries in a DOMAIN cache file on any of the name servers in either of the domains:

;
;cache file for all nameservers in both domains
;
; root name servers.
abc                              IN      NS      gobi.abc.
xyz                              IN      NS      kalahari.xyz.
gobi.abc.       3600000  IN      A       192.9.201.2
kalahari.xyz    3600000  IN      A       160.9.201.4

Files