ZyXEL Communications 200 Series - Manual (Page 318)

Chapter 16 Virtual Servers
ZyWALL USG 100/200 Series User’s Guide
318
NAT Loopback Virtual Server
When a LAN1 user sends SMTP traffic to IP address 1.1.1.1, the traffic comes into the
ZyWALL through the LAN1 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 WAN2. So you must configure a
similar virtual server rule for WAN2.
Figure 223 NAT Loopback Virtual Server
Click Network > Virtual Server and the + symbol and create the virtual server rule as shown
next. This virtual server rule is the same as in
NAT 1:1 Virtual Server on page 314 , except you
use the LAN1 interface instead of the WAN2 interface. This rule maps TCP port 25 (SMTP)
traffic destined for IP address 1.1.1.1 and coming in on WAN2 to the SMTP server (IP address
192.168.1.21). In this example the SMTP server also uses port 25, so the Mapped Port is set
to 25.
Figure 224 Create a Virtual Server
192.168.1.21
1.1.1.1
LAN1
192.168.1.89
Destination 1.1.1.1
NAT
SMTP
Destination 192.168.1.21
SMTP