Chapter 17 NAT

 

Table 93 Configuration > Network > NAT > Add (continued)

 

LABEL

DESCRIPTION

 

Firewall

By default the firewall blocks incoming connections from external

 

 

addresses. After you configure your NAT rule settings, click the Firewall

 

 

link to configure a firewall rule to allow the NAT rule’s traffic to come in.

 

 

The ZyWALL checks NAT rules before it applies To-ZyWALL firewall rules,

 

 

so To-ZyWALL firewall rules do not apply to traffic that is forwarded by

 

 

NAT rules. The ZyWALL still checks other firewall rules according to the

 

 

source IP address and mapped IP address.

 

 

 

 

OK

Click OK to save your changes back to the ZyWALL.

 

 

 

 

Cancel

Click Cancel to return to the NAT summary screen without creating the

 

 

NAT rule (if it is new) or saving any changes (if it already exists).

 

 

 

17.3 NAT Technical Reference

Here is more detailed information about NAT on the ZyWALL.

NAT Loopback

Suppose a NAT 1:1 rule maps a public IP address to the private IP address of a LAN SMTP e-mail server to give WAN users access. NAT loopback allows other users to also use the rule’s original IP to access the mail server.

 

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ZyWALL USG 50 User’s Guide