Chapter 20 Dns; Dns Overview; Dns Server Address Assignment; Dns Servers - ZyXEL Communications ZyWall 35 User Manual

This chapter shows you how to configure the DNS screens.

20.1 DNS Overview

DNS (Domain Name System) is for mapping a domain name to its corresponding IP address
and vice versa. The DNS server is extremely important because without it, you must know the
IP address of a machine before you can access it. The ZyWALL uses a system DNS server (in
the order you specify in the DNS System screen) to resolve domain names, for example, VPN,
DDNS and the time server.

20.2 DNS Server Address Assignment

The ZyWALL can get the DNS server addresses in the following ways.
1 The ISP tells you the DNS server addresses, usually in the form of an information sheet,
when you sign up. If your ISP gives you DNS server addresses, manually enter them in
the DNS server fields.
2 If your ISP dynamically assigns the DNS server IP addresses (along with the ZyWALL's
WAN IP address), set the DNS server fields to get the DNS server address from the ISP.
3 You can manually enter the IP addresses of other DNS servers. These servers can be
public or private. A DNS server could even be behind a remote IPSec router (see
Private DNS Server

20.3 DNS Servers

Use the DNS screen to configure the DNS server information that the ZyWALL sends to the
DHCP client devices on the LAN.
There are three places where you can configure DNS setup on the ZyWALL.
1 Use the DNS System screen to configure the ZyWALL to use a DNS server to resolve
domain names for ZyWALL system features like VPN, DDNS and the time server.
2 Use the DNS LAN screen to configure the DNS server information that the ZyWALL
sends to the DHCP client devices on the LAN.
3 Use the REMOTE MGMT DNS screen to configure the ZyWALL (in router mode) to
accept or discard DNS queries.

Chapter 20 DNS

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