Figure 188 Create A Policy Route; Figure 189 Nat Loopback Successful - ZyXEL Communications ZyWALL USG 300 User Manual

Chapter 16 Virtual Servers

Figure 188 Create a Policy Route

Now the LAN SMTP server replies to the ZyWALL's LAN IP address and the ZyWALL
changes the source address to 1.1.1.1 before sending it to the LAN user's computer. The
source in the return traffic matches the original destination address (1.1.1.1) and the LAN user
can use the LAN SMTP server.

Figure 189 NAT Loopback Successful

NAT
Source 192.168.1.21
Source 1.1.1.1
SMTP
SMTP
LAN
192.168.1.21 192.168.1.89
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