The Default Many-To-One Outbound Nat Policy - SonicWALL SonicOS Enhanced 2.2 Administrator's Manual

The NAT Policies page allows you to view your NAT Policies by Custom Policies, Default Policies, or
All Policies.
Alert!
Before configuring NAT Policies, be sure to create all Address Objects associated with the policy. For
instance, if you are creating a One-to-One NAT policy, be sure you have Address Objects for your public
and private IP addresses.
Tip!
By default, LAN to WAN has a NAT policy predefined on the SonicWALL.

The Default Many-to-One Outbound NAT Policy

The default Many-to-One Outbound NAT policy is visible as Any -> WAN Primary IP in either Custom
Policies or All Policies. It translates any source to the WAN Primary IP as the traffic goes out to the
Internet. The Destination and Service are not translated. The default policy is listed also with a source
interface of X0 and a destination interface of X1. This policy allows your computers on internal interfaces
in the LAN and DMZ zones to communicate with hosts on the Internet by sharing the WAN public IP
address. This policy is always available, even if you want to run customized NAT policies for certain
services or for certain address objects or interfaces, but it can be changed, disabled or deleted. There are
other default NAT Policies created automatically which relate to the network interfaces, and to IKE VPNs.
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