Dynamic DNS allows external clients to connect to your UniFi gateway using a hostname rather than an IP address. This is particularly useful if your UniFi gateway uses a frequently changing WAN IP as a result of DHCP assignment.
Relying on a dynamic WAN IP to facilitate gateway connections when used as a VPN server forces users to constantly reconfigure their clients to ensure they are using the correct address.
Dynamic DNS solves this by:
- Utilizing hostnames, which are inherently easier to remember compared to complex IPs.
- Authorizing connections with a single hostname, regardless of when (or how often) the corresponding WAN IP changes.
Your UniFi gateway must have a public IP address for Dynamic DNS to work properly. The following IP addresses will prohibit the use of 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)
An IP address in the above ranges can be resolved either by setting your upstream router to Bridge Mode, or by contacting your Internet service provider.
Configuring Dynamic DNS
Begin by creating an account with a supported Dynamic DNS provider, such as: afraid, dnspark, dslreports, dyndns, easydns, namecheap, noip, sitelutions, or zoneedit.
Note: Other providers may work, but are not officially supported.
After obtaining a hostname from your provider, create a Dynamic DNS entry in the Internet settings of your UniFi Network application. You will need to enter the:
- Service - The name of your service provider.
- Hostname - The fully qualified domain name (FQDN) given to you by your Dynamic DNS provider, or derived from a personal/business domain you are using for this purpose (e.g., myhostname.ddns.com or myhostname.com).
- Username - The username you registered with your provider.
- Password - The password you registered with your provider.
- Server (optional) - This is only required for certain providers and specifies where UniFi updates your Dynamic DNS server of WAN IP changes. Please consult your provider’s documentation to see if this is a necessary input for you when using an Inadyn-based client.
Once configured, clients connecting to the UniFi gateway using a VPN or forwarded port can reference the Dynamic DNS hostname instead of the public IP address.
The inability of your Dynamic DNS hostname to resolve to the correct WAN IP address may be a result of the following:
Your UniFi gateway is located behind another router/modem that uses Network Address Translation (NAT).
If you have an upstream router or modem, you should place it in bridge mode. Otherwise, please contact your Internet service provider.
You have entered invalid credentials, or an invalid hostname.
Make sure you accurately enter all fields into the Network application. Also make sure that you are using the correct hostname when configuring client devices.
Changes in your WAN IP address are not being received by the Dynamic DNS provider’s server.
UniFi supports many Dynamic DNS providers and sends updates automatically without requiring you to enter any further information. Some providers, however, require you to enter the server to which IP address updates should be sent. If you are unsure, you should consult your provider to inquire about the requirements for configuring an inadyn-based client.