Dynamic DNS for UMR
Dynamic DNS (DDNS) allows external clients to connect to your UniFi Mobile Router (UMR) using a hostname instead of relying on a dynamic WAN IP address. This is especially useful when your UMR receives frequently changing IPs via DHCP from your Internet Service Provider (ISP).
If you're using the UMR as a VPN server, or need remote access to your network, depending on a changing IP can be unreliable—forcing users to constantly update their connection settings.
DDNS solves this problem by:
Assigning a consistent, easy-to-remember hostname to your UMR.
Automatically updating that hostname when your WAN IP changes, maintaining reliable remote connectivity.
What You Need to Know Before Using Dynamic DNS (DDNS)
To ensure DDNS works properly, your UMR must be reachable via a public IP address — this means either:
- A public IP is directly assigned to the UMR,
- UMR is behind a router that has a public IP, and that upstream router is configured with port forwarding to the UMR.
Note:
- If neither condition is met — for example, if the UMR is behind CG-NAT or double NAT without port forwarding — DDNS will not function correctly because inbound connections cannot reach the device.
- A DDNS profile can only be assigned to one device. WAN interfaces will share the same DDNS profile.
The following IP address ranges indicate private or Carrier-Grade NAT (CG-NAT) IPs, which are not compatible with Dynamic DNS:
- 10.0.0.0/8 (10.0.0.0 - 10.255.255.255)
- 172.16.0.0/12 (172.16.0.0 - 172.31.255.255)
- 192.168.0.0/16 (192.168.0.0 - 192.168.255.255)
- 100.64.0.0/10 (100.64.0.0 - 100.127.255.255)
If your UMR’s WAN IP falls within one of these ranges, DDNS will not be able to establish remote access successfully.
You can try the following solutions:
Option 1: Assign a Public IP Directly to UMR
This is the simplest and most reliable solution. Use a mobile data plan or SIM card that provides a public IP address directly to your UMR.
- UMR connects directly to the internet with a public IP.
- DDNS can accurately update your reachable IP address.
- External devices can connect directly via the DDNS domain name.
- No complex network configuration required — this is the most stable approach.
Option 2 (Advanced): UMR Behind a Router (with Port Forwarding)
If you need to deploy UMR behind an existing router, ensure that the upstream router has a public IP and configure port forwarding.
- Set up port forwarding on the upstream router to redirect external traffic to UMR’s local IP address.
- Make sure DDNS updates reflect the external IP
- Suitable for advanced users who need to maintain an existing network structure.
Configuring Dynamic DNS
The DDNS service periodically updates the IP address information of the hostname, making sure that the device remains reachable via the same hostname even in cases when its IP address has changed.
Begin by creating an account with a supported Dynamic DNS provider, such as: afraid, dyndns, noip, or duckdns.
Note: Other providers may work, but are not officially supported.
After obtaining a hostname from your provider, configure Dynamic DNS in UMR’s Internet settings.
- Navigate to: Settings > Dynamic DNS
- Enter the following information:
Field | Description |
| Select device | Select the device you would like to apply this DDNS profile to. Alternatively, you can create a DDNS profile first and apply it later through the device side panel: Device List > Click Device > Settings > Dynamic DNS. |
| Service | Select your DDNS provider from the list. |
| Hostname | Enter the fully qualified domain name (FQDN) given by your DDNS provider (e.g., myhostname.ddns.net). |
| Username | Your registered username with the DDNS provider. |
| Password/API Key | The password or API key provided by your DDNS provider. |
| Server (Optional) | Some providers require you to specify an update server for IP changes. Check with your provider’s documentation. |
- Click "Save" to apply your settings.
Once configured, clients connecting to the UMR via VPN or port forwarding can use the Dynamic DNS hostname instead of the public IP to access the device.
Example of UMR configuration for setting up corresponding DDNS servers:
- DuckDNS
| Field | UMR DDNS Input |
| Service | Select “DuckDNS” |
| Hostname | {your-domain-name}.duckdns.org |
| Username | {your-account} |
| Password/API Key | {API token from duckdns web} |
- No-IP
| Field | UMR DDNS Input |
| Service | Select “No-IP” |
| Hostname | {No-IP Hostname} |
| Username | {DDNS Keys > Username} |
| Password/API Key | {DDNS Keys > Password} |
- Afraid ( FreeDDNS)
| Field | UMR DDNS Input |
| Service | Select “Afraid” |
| Hostname | {Subdomains>Hostname} |
| Username | {Afraid Login UserID} |
| Password/API Key | {Afraid Login User password} |
- DynDNS
| Field | UMR DDNS Input |
| Service | Select “Dyndns” |
| Hostname | {Dyn DNS HostName} |
| Username | {Account Settings > Username } |
| Password/API Key | {Account Settings > Client Key } |
Note: Different services have different required fields. Please fill them out according to the specific requirements of your DDNS provider.
Troubleshooting
If your Dynamic DNS hostname does not resolve correctly, consider the following potential causes:
UMR is Behind a NAT Router
If your UMR is connected behind another router or modem using NAT, it may not be able to update the public IP correctly.
Solution: Set the upstream router/modem to Bridge Mode or request a public IP from your ISP.
Invalid Credentials or Hostname
Ensure you have entered the correct DDNS account details:
- Double-check your username, password, and hostname in the UMR DDNS settings.
- Verify that your DDNS provider account is active and properly configured.
DDNS Provider Not Receiving IP Updates
If your Dynamic DNS hostname is not updating with the correct IP:
- Some providers require you to enter a specific update server. Ensure you have entered this correctly if needed.
- Check if your ISP frequently changes IP addresses—some ISPs cycle through multiple CG-NAT IPs, which may cause issues.