PLANET CS-2000 - Manual (Page 477)

CS-2000 UTM Content Security Gateway User’s Manual
- 471 -
Advanced Description
The so called DNS mapped represents the domain is managed by which DNS server, and all the domain
name internet records are recorded in the DNS host. For example, the real IP address in web site or mail
server, so the DNS server must correctly link to internet and its DNS record must be correct.
According to the international rule, the DNS must correspond to two DNS server, in order to assure
the network stability. Both of the DNS servers can provide the backup function if any of them breaks down.
On the other hand, the backup function not only assures the internet stability but also ensure the fluency of
the user to use the domain name.
Example：
We can set a server which applied the following situation.
1． To register a domain name called test.net.tw.
2． The primary server IP is 61.11.11.11. Host name is dns1.test.net.tw.
The secondary server IP is 211.22.22.22. Host name is dns2.test.net.tw.
3． Prepare the internet leased line or ADSL to link to internet.
4． The server to analyzed ：
www.test.net.tw (192.168.1.100) web server
mail.test.net.tw (192.168.1.101) e-mail server
First of all, we must apply two ADSL static IP (or Network Leased Line) from the ISP.
The IP address are：
61.11.11.10 ~ 61.11.11.14
211.22.22.18 ~ 211.22.22.30
To register the DNS setting from the address register web site.
Primary host server
Host name：dns1.test.net.tw
IP address：61.11.11.11
Secondary host server
Host name：dns2.test.net.tw
IP address：211.22.22.22
＊ The DNS domain name applied from the registered web site, which must be correspond
to the static IP.