ZyXEL Communications ZYWALL10 User Manual
ZyWALL 10 Internet Security Gateway
Example Firewall Rules
19-1
Chapter 19
Example Firewall Rules
This chapter gives examples for configuring various rules for WAN to LAN and LAN to WAN.
19.1 Examples
Whenever you open a hole in the firewall to forward a service from the Internet to the local network, and
NAT is also enabled, you may have to also configure a server behind NAT using SMT menu 15.2. Please
see the NAT chapter for more detailed information and also see Figure 14-5 for a view of how filtering, the
firewall and NAT interact.
NAT is also enabled, you may have to also configure a server behind NAT using SMT menu 15.2. Please
see the NAT chapter for more detailed information and also see Figure 14-5 for a view of how filtering, the
firewall and NAT interact.
19.1.1 Example 1: Firewall Rule To Allow Web Service From The Internet
Let’s say you have one server on the local network, with an IP of 10.100.1.2, supporting FTP, HTTP,
Telnet and mail services. The only traffic allowed from the Internet is web service. You want to be able to
forward all traffic initiated from the local network. You want to know who accesses your server and send e-
mail alerts when this happens. Assume, for example, your mail account is
Telnet and mail services. The only traffic allowed from the Internet is web service. You want to be able to
forward all traffic initiated from the local network. You want to know who accesses your server and send e-
mail alerts when this happens. Assume, for example, your mail account is
user@zyxel.com
. Another
network administrator has an e-mail address of
user2@zyxel.com
. Here are the steps you would follow.