- The article explains how to identify and fix double NAT on USG using different methods, such as removing the second router, enabling bridge mode on the modem or gateway, or enabling access point mode on the second router.
- The article also answers some frequently asked questions about double NAT and USG, such as the disadvantages of double NAT, how to check and set up port forwarding or UPnP on USG, and how to fix double NAT without changing any settings on the devices.
- The article concludes by stating that double NAT is a common issue that can affect the network performance and online experience, but it is not hard to fix double NAT on USG using one of the methods discussed in the article.
If you have a UniFi Security Gateway (USG) in your network, you may encounter a common issue called double NAT. Double NAT happens when two devices on your network, such as your modem and your router, both perform network address translation (NAT). NAT is a process that allows multiple devices to share a single public IP address and access the internet. However, having two devices doing NAT can cause problems with some online services that require port forwarding or UPnP, such as gaming, VoIP, or remote access.
In this article, we will explain how to identify and fix double NAT on USG using different methods. We will also answer some frequently asked questions about double NAT and USG.
Table of Contents
How to Identify Double NAT on USG
Before you try to fix double NAT on USG, you need to confirm that you actually have this issue. There are a few ways to do this:
- Check your network settings on your USG controller. If you see a warning message that says “Double NAT detected”, then you have double NAT on USG.
- Check your WAN IP address on your USG and compare it with your public IP address. You can find your WAN IP address on your USG controller under Devices > USG > Properties > Config > WAN. You can find your public IP address by visiting a website like What Is My IP Address. If your WAN IP address and your public IP address are different, then you have double NAT on USG.
- Check your modem or gateway settings and see if it has a built-in router or firewall. You can usually access your modem or gateway settings by typing its IP address into your web browser. The default IP address is often 192.168.0.1 or 192.168.1.1, but it may vary depending on your device model and manufacturer. You can also check the user manual or the sticker on the device for the IP address and login credentials. If your modem or gateway has a router or firewall feature enabled, then it is likely performing NAT and causing double NAT on USG.
How to Fix Double NAT on USG
There are three main methods to fix double NAT on USG:
- Remove the second router
- Enable bridge mode on the modem or gateway
- Enable access point mode on the second router
We will explain each method in detail below.
Solution 1: Remove the Second Router
The simplest way to fix double NAT on USG is to remove the second router from your network. This means that you only have one device performing NAT: your modem or gateway. Your USG will then connect directly to your modem or gateway and receive a public IP address.
To remove the second router from your network, follow these steps:
Step 1: Disconnect the power cable from the second router.
Step 2: Disconnect the ethernet cable that connects the second router’s WAN port to the modem or gateway’s LAN port.
Step 3: Connect the ethernet cable that was connected to the second router’s WAN port to the USG’s WAN port.
Step 4: Reconnect the power cable to the modem or gateway and wait for it to boot up.
Step 5: Reconnect the power cable to the USG and wait for it to boot up.
Step 6: Check your network settings on your USG controller and see if the double NAT warning is gone.
Solution 2: Enable Bridge Mode on the Modem or Gateway
Another way to fix double NAT on USG is to enable bridge mode on your modem or gateway. Bridge mode is a feature that disables the router and firewall functions of your modem or gateway and turns it into a simple pass-through device. This means that it will not perform NAT and will not assign any private IP addresses to your devices. Your USG will then connect directly to the internet and receive a public IP address.
To enable bridge mode on your modem or gateway, follow these steps:
Step 1: Log in to your modem or gateway settings by typing its IP address into your web browser.
Step 2: Find the option to enable bridge mode or disable router/firewall functions. The location and name of this option may vary depending on your device model and manufacturer. You may need to look under advanced settings, network settings, internet settings, or WAN settings.
Step 3: Enable bridge mode or disable router/firewall functions and save the changes.
Step 4: Reboot your modem or gateway and wait for it to boot up.
Step 5: Check your network settings on your USG controller and see if the double NAT warning is gone.
Solution 3: Enable Access Point Mode on the Second Router
The third way to fix double NAT on USG is to enable access point mode on your second router. Access point mode is a feature that disables the router functions of your second router and turns it into a simple wireless extender. This means that it will not perform NAT and will not assign any private IP addresses to your devices. Your USG will then connect directly to your modem or gateway and receive a public IP address.
To enable access point mode on your second router, follow these steps:
Step 1: Log in to your second router settings by typing its IP address into your web browser.
Step 2: Find the option to enable access point mode or disable router functions. The location and name of this option may vary depending on your device model and manufacturer. You may need to look under wireless settings, network settings, internet settings, or LAN settings.
Step 3: Enable access point mode or disable router functions and save the changes.
Step 4: Reboot your second router and wait for it to boot up.
Step 5: Check your network settings on your USG controller and see if the double NAT warning is gone.
Frequently Asked Questions About Double NAT and USG
Here are some common questions and answers about double NAT and USG:
Question: What are the disadvantages of double NAT?
Answer: Double NAT can cause issues with some online services that require port forwarding or UPnP, such as gaming, VoIP, or remote access. Port forwarding and UPnP are techniques that allow devices on your network to communicate with devices on the internet by opening specific ports on your router. However, with double NAT, you have two routers that need to open the same ports, which can cause conflicts and errors. Double NAT can also make it harder to troubleshoot network problems and monitor network traffic.
Question: How can I check if port forwarding or UPnP is working on my USG?
Answer: You can check if port forwarding or UPnP is working on your USG by using a website like Port Checker or YouGetSignal. These websites allow you to test if a specific port is open on your public IP address. You can also check the port forwarding and UPnP settings on your USG controller under Devices > USG > Properties > Config > Port Forwarding and Devices > USG > Properties > Config > UPnP.
Question: How can I set up port forwarding or UPnP on my USG?
Answer: You can set up port forwarding or UPnP on your USG by using the USG controller. To set up port forwarding, go to Devices > USG > Properties > Config > Port Forwarding and click on Create New Port Forward Rule. Then, enter the name, protocol, external port, internal IP address, and internal port of the device or service you want to forward. To set up UPnP, go to Devices > USG > Properties > Config > UPnP and enable the option for Enable UPnP LAN.
Question: How can I fix double NAT without changing any settings on my devices?
Answer: If you don’t want to change any settings on your devices, you can try using a VPN service to bypass double NAT. A VPN service is a software that encrypts your internet traffic and routes it through a remote server. This way, you can avoid the NAT issues caused by your routers and access online services that require port forwarding or UPnP. However, using a VPN service may affect your internet speed and performance, so you should choose a reliable and fast VPN service.
Conclusion
Double NAT is a common issue that can affect your network performance and online experience. However, it is not hard to fix double NAT on USG using one of the methods we discussed in this article. By removing the second router, enabling bridge mode on the modem or gateway, or enabling access point mode on the second router, you can eliminate double NAT on USG and enjoy a smooth and secure network.
We hope this article was helpful for you. If you have any questions or feedback, please leave a comment below.
Disclaimer: This article is for informational purposes only and does not constitute professional advice. We are not affiliated with any of the products or services mentioned in this article. We recommend that you consult with a qualified network technician before making any changes to your network settings.