Address Record; Dns Wildcard; Name Server Record; Private Dns Server - ZyXEL Communications ZyWall 70 User Manual

ZyWALL 70 User's Guide

21.4 Address Record

An address record contains the mapping of a fully qualified domain name (FQDN) to an IP
address. An FQDN consists of a host and domain name and includes the top-level domain. For
example, www.zyxel.com.tw is a fully qualified domain name, where "www" is the host,
"zyxel" is the second-level domain, and "com.tw" is the top level domain.
mail.myZyXEL.com.tw is also a FQDN, where "mail" is the host, "myZyXEL" is the second-
level domain, and "com.tw" is the top level domain.
The ZyWALL allows you to configure address records about the ZyWALL itself or another
device. This way you can keep a record of DNS names and addresses that people on your
network may use frequently. If the ZyWALL receives a DNS query for an FQDN for which
the ZyWALL has an address record, the ZyWALL can send the IP address in a DNS response
without having to query a DNS name server.

21.4.1 DNS Wildcard

Enabling the wildcard feature for your host causes *.yourhost.com to be aliased to the same IP
address as yourhost.com. This feature is useful if you want to be able to use, for example,
www.yourhost.com and still reach your hostname.

21.5 Name Server Record

A name server record contains a DNS server's IP address. The ZyWALL can query the DNS
server to resolve domain names for features like VPN, DDNS and the time server. A domain
zone may also be included. A domain zone is a fully qualified domain name without the host.
For example, zyxel.com.tw is the domain zone for the www.zyxel.com.tw fully qualified
domain name.

21.5.1 Private DNS Server

In cases where you want to use domain names to access Intranet servers on a remote private
network that has a DNS server, you must identify that DNS server. You cannot use DNS
servers on the LAN or from the ISP since these DNS servers cannot resolve domain names to
private IP addresses on the remote private network.
The following figure depicts an example where three VPN tunnels are created from ZyWALL
A; one to branch office 2, one to branch office 3 and another to headquarters (HQ). In order to
access computers that use private domain names on the HQ network, the ZyWALL at branch
office 1 uses the Intranet DNS server in headquarters.
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