Description | This article describes that the Nintendo Switch console supports NAT type A or B to play with other people online. |
Scope | FortiGate. |
Solution |
Outgoing firewall policy with SNAT enabled gives either NAT C or NAT D type, but game consoles like the Nintendo Switch require NAT type A or type B to play with other people online.
Nintendo NAT types: Type A: The Switch can communicate online without any restrictions. Type B: The Switch can communicate online with minor restrictions. Type C: The Switch can communicate online with moderate restrictions Type D: The Switch can communicate online with moderate restrictions. NAT type D can communicate only with other units which are on NAT type A. Type F: Cannot communicate with anyone online.
Solution:
Enable Preserve Source Port on the firewall policy gives NAT type B.
Note: 'Preserve Source Port' is enabled by default from FortiOS 7.4.4 Onward. For more information, see Fine-tuning source port behavior for SNAT - FortiGate 7.4.0 new features. |
The Fortinet Security Fabric brings together the concepts of convergence and consolidation to provide comprehensive cybersecurity protection for all users, devices, and applications and across all network edges.
Copyright 2025 Fortinet, Inc. All Rights Reserved.