dyndns

Dynamically update your host DNS records, either via an HTTP endpoint or RFC 2136.

Requirements

• Python 3.6 or greater.
• For HTTP mode: an HTTP endpoint that accepts the JSON update protocol (e.g. https://dyndns.limau.net/update).
• For RFC 2136 mode: a DNS server configured to accept dynamic updates, a configured zone, and an authorized TSIG key. Requires DNSPython and netifaces.

Configuration file

The config file is a JSON file (conventionally config.json). The update mode is selected automatically based on which keys are present:

• If endpoint and bearer_token are present → HTTP mode
• Otherwise → RFC 2136 mode

See config.example.json (HTTP) and examples/config.json (RFC 2136) for starter templates.

Common options

key	type	description
zone	string	The zone name being updated, e.g. home.example.com.
host	string	The primary record name to set or update, e.g. myhost.
alt_names	array	(Optional) list of other names to alias to this host via CNAME.
has_bonjour	boolean	(Optional, default: false) Update the host-wa AAAA record with the local Bonjour/utun0 address.
has_local	boolean	(Optional, default: false) Update the host-local A record with the LAN address.
use_ipv6_slaac	boolean	(Optional, default: false) Prefer the stable SLAAC address for IPv6 over the public privacy address.
debug	boolean	(Optional, default: false) Print config, operations, and responses at runtime.
urllib_timeout	int	(Optional, default: 10) HTTP request timeout in seconds.

HTTP mode options

key	type	description
endpoint	string	The HTTPS update endpoint URL, e.g. https://dyndns.limau.net/update.
bearer_token	string	Bearer token for authorization.

RFC 2136 mode options

key	type	description
zone_master	string	The primary DNS server to send updates to (hostname or IP).
tsigkeyring	dict	Required fields: name, secret, and keyalgorithm. Valid algorithms: hmac-md5, hmac-sha256, hmac-sha512.
dnspython_timeout	int	(Optional, default: 10) DNS TCP timeout in seconds.

Usage

$ python3 nsupdate.py <path to config.json>

Optionally build with PyInstaller to create a bundled Python application.