Azure DDNS

Provides an Inadyn compatible DynDNS2 API to be hosted by an Azure Function which uses an underlying Microsoft Azure hosted DNS Zone to maintain the IP address for a single A record.

Deploying the Provider

Within the Microsoft Azure Function portal:

1. Create a new Azure Function.
2. Open the Configuration pane, and add the following application settings:
   • AppUsername - This is the username that will be required to use the public endpoint.
   • AppPassword - This is the password that will be required to use the public endpoint.
   • DnsZoneRGName - This will need to contain the Resource Group Name for your DNS Zone.
3. Open the Identity pane, and enable a System or User Assigned identity. This identity MUST have DNS Zone Contributor role for the DNS Zone the provider will be responsible for modifying.
4. Deploy this codebase into your Azure Function.

NOTE: Because this provider uses Basic authentication, a colon (:) will not be supported as a character in the AppPassword application setting.

Configuring the Inadyn Client

The following file will need to be updated on the network device at the location: /etc/inadyn.conf. If you are using a device such as a Unifi Dream Machine or Dream Machine Pro, the file will instead be located at: /run/ddns_eth{?}_inadyn.conf.

custom your-ddns.azurewebsites.net:1 {
    hostname    = "your.azuredomain.com"
    username    = "REDACTED"
    password    = "REDACTED"
    ddns-server = "your-ddns.azurewebsites.net"
    ddns-path   = "/nic/update?hostname=%h&myip=%i"
}

Provider Options

• hostname: This MUST be the FQDN of the DNS entry to update.
• username: This MUST match the username used in the AppUsername application configuration setting.
• password: This MUST match the password used in the AppPassword application configuration setting.
• ddns-server: This is the location where the Azure Function has been deployed.
• ddns-path: DO NOT CHANGE!

Testing

To test this, you will need to have command line access to the device running the inadyn.service.

inadyn -1n --force --loglevel=DEBUG --config=/etc/inadyn.conf

The following snippet shows what you should see on the Inadyn client logs when communicating with your DDNS service:

inadyn[527119]: Sending alias table update to DDNS server: GET /nic/update?hostname=your.azuredomain.com&myip=REDACTED HTTP/1.0
inadyn[527119]: Host: your-ddns.azurewebsites.net
inadyn[527119]: Authorization: Basic REDACTED
inadyn[527119]: User-Agent: inadyn/2.9.1 https://github.com/troglobit/inadyn/issues
inadyn[527119]: Successfully sent HTTPS request!
inadyn[527119]: Successfully received HTTPS response (205/8191 bytes)!
inadyn[527119]: DDNS server response: HTTP/1.1 200 OK
Connection: close
Content-Type: text/plain; charset=utf-8
Date: Sun, 31 Dec 2023 02:16:13 GMT

good
inadyn[527119]: Successful alias table update for your.azuredomain.com => new IP# REDACTED
inadyn[527119]: Updating cache for your.azuredomain.com