Learn about Dynamic DNS

Dynamic DNS allows you to direct your domain or a subdomain to a resource that is behind a gateway that has a dynamically assigned IP address.

Set up Dynamic DNS with Google Domains to:

• Create an A or AAAA record for your domain or subdomain that lets the Google name servers know to expect a dynamic IP
• Generate a username and password your host or server uses to communicate the new IP address to the Google name servers

After you set up Dynamic DNS, you must set up a client program on your host, server, or gateway that:

• Detects IP address changes
• Uses the generated username and password
• Communicates the new address to the Google name servers

Important: Dynamic DNS works with IPv4 and IPv6 addresses, but not at the same time.

Set up Dynamic DNS

1. On your computer, sign in to Google Domains.
2. Select the name of your domain.
3. At the top left, click Menu DNS. “Google Domains (Active)” should be selected.
   • Tip: If “Custom (Active)” is selected, you already have custom name servers and can't use Google Domains’ Dynamic DNS service.
4. Scroll to “Dynamic DNS.”
5. Click Manage dynamic DNS Create new record.
6. To assign a Dynamic IP, enter the name of the subdomain or root domain.
7. Click Save.

Other options to manage Dynamic DNS:

• To view the record values: Click the triangle next to the record.
• To view the username and password created for this record: Click View Credentials.
• To configure your gateway or client software to contact the Google name servers: Use the username and password created for the record.
• To delete the record: Scroll to “Resource records,” click the triangle next to “Dynamic DNS,” then Delete.

Set up a client program on your gateway, host, or server

There are several popular dynamic DNS clients in use, such as DDclient and INADYN. In addition, most routers have software built in to detect IP changes and communicate them with the name servers.

Important: Google Domains uses the dyndns2 protocol.

Configure your dynamic DNS client with:

• Provider or DNS or Service: The name of your DNS Provider.
• Username or credential: The generated username in the Dynamic DNS record.
• Password or credential: The generated password in the Dynamic DNS record.

After you create the record and configure your client software, test the record. Enter the subdomain and domain into a web browser, or appropriate client, and make sure they connect to the correct resource.

Examples

DDclient now has support for Google Domains.

DDclient with Google Domains Support

ddclient.conf entries: ssl=yes protocol=googledomains login=generated_username password=generated_password your_resource.your_domain.tld

General client configuration examples:

DDclient without Google Domains support	INADYN
Sample ddclient.conf entries: protocol=dyndns2 use=web server=domains.google.com ssl=yes login=generated_username password=generated_password your_resource.your_domain.tld	Add the following to your inadyn.conf system [e-mail] username generated_username password generated_password alias sub.domain.tld

Use the API to update your Dynamic DNS record

Dynamic DNS client software automatically updates your dynamic DNS record. You can perform manual updates with the API by making a POST request or GET to the following URL:

https://domains.google.com/nic/update

The API requires HTTPS. Here’s an example request:

https://username:[e-mail]/nic/update?hostname=subdomain.yourdomain.com&myip=1.2.3.4

Important: You must also set a user agent in your request. During a test with the URL directly above, web browsers generally add a user agent for you. The final HTTP query sent to our servers should be similar to this:

Example HTTP query:

POST /nic/update?hostname=subdomain.yourdomain.com&myip=1.2.3.4 HTTP/1.1
Host: domains.google.com
Authorization: Basic base64-encoded-auth-string User-Agent: Chrome/41.0 [e-mail]

Request Parameters:

Parameter	Required or Optional	Description
username:password	Required	The generated username and password associated with the host that is to be updated.
hostname	Required	The hostname to be updated.
myip	Optional for IPv4. Required if you have an IPv6 address.	The IP address to which the host is set. If not supplied, we use the IP of the agent that sent the request. Important: If your agent uses an IPv6 address, myip is required. You can check your agent’s IP address at: https://domains.google.com/checkip.
offline	Optional	Sets the current host to offline status. If an update request is performed on an offline host, the host is removed from the offline state. Allowed values are: yes no

After the request is processed, one of the following responses is returned.

Make sure you interpret the response correctly, or you risk blocking your client from our system.

Response	Status	Description
good {user’s IP address}	Success	The update was successful. You should not attempt another update until your IP address changes.
nochg {user’s IP address}	Success	The supplied IP address is already set for this host. You should not attempt another update until your IP address changes.
nohost	Error	The hostname doesn't exist, or doesn't have Dynamic DNS enabled.
badauth	Error	The username/password combination isn't valid for the specified host.
notfqdn	Error	The supplied hostname isn't a valid fully-qualified domain name.
badagent	Error	Your Dynamic DNS client makes bad requests. Ensure the user agent is set in the request.
abuse	Error	Dynamic DNS access for the hostname has been blocked due to failure to interpret previous responses correctly.
911	Error	An error happened on our end. Wait 5 minutes and retry.
conflict A conflict AAAA	Error	A custom A or AAAA resource record conflicts with the update. Delete the indicated resource record within the DNS settings page and try the update again.