NGFW policy mode and NAT
If your FortiGate is operating in NAT mode, rather than enabling source NAT in individual NGFW policies, go to Policy & Objects > Central SNAT and add source NAT policies that apply to all matching traffic. In many cases, you may only need one SNAT policy for each interface pair. For example, if you allow users on the internal network (connected to LAN) to browse the Internet (connected to wan1), you can add a LAN to wan1 Central SNAT policy similar to the following.
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