Chapter 16 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 223 NAT Loopback Virtual Server

 

 

NAT

1.1.1.1

 

 

 

 

 

 

 

Destination 192.168.1.21

Destination 1.1.1.1

 

 

 

 

 

 

 

SMTP

 

 

SMTP

 

LAN1

192.168.1.21192.168.1.89

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

318

 

ZyWALL USG 100/200 Series User’s Guide