Chapter 16 Virtual Servers

Figure 217 NAT 1:1 Example Virtual Server

 

 

 

 

LAN1 Destination 192.168.1.21

Destination 1.1.1.1

 

SMTP

NAT

 

SMTP

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

192.168.1.21

The wan2 interface has a different IP address than 1.1.1.1, so in order for the ZyWALL gateway to be able to do ARP resolution correctly, you need to create a wan2 virtual server entry. In the Network > Virtual Server screen, click the + symbol and create a new virtual server entry as shown next. This entry maps TCP port 25 (SMTP) traffic coming to IP address 1.1.1.1 on wan2 to the IP address of the SMTP server (192.168.1.21 defined in the LAN_SMTP object). In this example the SMTP server also uses port 25, so the Mapped Port is set to 25. The following sections describe how to manually configure corresponding policy routes for NAT 1:1 mapping and loopback so the options to have the ZyWALL automatically create them are not selected here.

Figure 218 Create a Virtual Server

NAT 1:1 Policy Route

This section sets up a policy route for the traffic coming from the LAN1 SMTP server to the ZyWALL’s lan1 interface. It changes the source address from 192.168.1.21 to 1.1.1.1. This is also called Source NAT (SNAT). It sends the traffic out through the wan2 interface.

 

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