Nat Loopback Virtual Server; Figure 98 Nat Loopback Virtual Server; Figure 99 Create A Virtual Server - ZyXEL Communications Unified Security Gateway ZyWALL 1000 User Manual

Chapter 6 Tutorials

6.7.1 NAT Loopback Virtual Server

When a LAN user sends SMTP traffic to IP address 1.1.1.1, the traffic comes into the
ZyWALL through the ge1 (LAN) interface, thus it does not match the NAT 1:1 mapping's
virtual server rule for SMTP traffic coming to IP 1.1.1.1 from ge3 (the WAN). So you must
configure a similar virtual server rule for ge1.

Figure 98 NAT Loopback Virtual Server

Destination 192.168.1.21
Click Network > Virtual Server and the + symbol and create the virtual server rule as shown
next. This virtual server rule is the same as the NAT 1:1 virtual rule in
149, except you use the LAN interface (ge1) instead of the WAN interface (ge3). This rule
maps TCP port 25 (SMTP) traffic destined for IP address 1.1.1.1 and coming in on ge1 to the
IP address of the SMTP server (192.168.1.21). In this example the SMTP server also uses port
25, so the Mapped Port is set to 25.

Figure 99 Create a Virtual Server

152
NAT
1.1.1.1
SMTP
LAN
192.168.1.21
Destination 1.1.1.1
SMTP
192.168.1.89
Section 6.6.2 on page
ZyWALL USG 1000 User's Guide