ZyXEL Communications ZyWall USG 50-H Series User Manual page 266

Chapter 14 Virtual Servers
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 201 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 in
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 202 Create a Virtual Server
266
1.1.1.1
SMTP
LAN
192.168.1.21
Destination 1.1.1.1
SMTP
192.168.1.89
NAT 1:1 Virtual Server on page
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