Shell DDNS Client

This is a DDNS client with minimal requirements.

• posix-compatible shell (tested with bash on Fedora)
• glibc or dig for DNS queries
• curl for API calls (raise an issue if you need wget support)

Usage

• Download the ddns-client.sh script and make it executeable
• Set required parameters as ENV variable (see here)
• Run script

Providers

DDNS Updates

• Cloudflare: Update IPs ind Cloudflares DNS API

Query Public IP

• Cloudflare (default): Using Cloudflares 1.1.1.1 DNS Server

Query DNS

• getent (default): Part of glibc
• dig

Reference

ℹ️ Note: All parameters must be set as ENV variables. There are no CLI-Arguments

General Parameters:

Name	Description
DDNS_MODE	lazy-update: check first, update only when required update-now: Perform DDNS Update check: Check if DDNS update is required help (default): print help noop: Do nothing. Allows script includes
DDNS_CONF	Source/Read a file at startup and set ENV variables. NOTE: The config-file is executed as a shel script!
DDNS_LOG_LEVEL	0...Only Fatal Errors 1...Info: Log important steps 2...Debug1: Log human-readable debug info 3...Debug2: Everything, including dumps
DDNS_IP_PROVIDER	Set Public-IP-Query-Service
DDNS_PROVIDER	DDNS_SERVICE
DDNS_HOSTNAMES	List of hostnames (no domain) to update
DDNS_DOMAIN	Your domain
DDNS_QUERY	Query spcific DNS entry (must be FQDN) to check if DDNS-update is required.

Cloudflare (DDNS_PROVIDER=cloudflare):

Name	Description
DDNS_CF_AUTHTYPE	Use token or key authentication"
DDNS_CF_TOKEN	Token. Permissions nedded: All Zones Read, DNS Edit"
DDNS_CF_APIUSER	Cloudflare Username for apikey authentication"
DDNS_CF_APIKEY	Cloudflare API Key for apikey authentication"

Testing

We are using BASH Automated Testing System.

# Make executable
make

# Run Tests
make test