ddclient

ddclient is a Perl client that keeps DNS records up to date when your public IP address changes. It supports a wide range of Dynamic DNS services and DNS provider APIs, and can run periodically or as a daemon to continuously refresh records.

Key Features

• Updates dynamic DNS entries for many DDNS services and DNS providers
• Multiple ways to detect external IP (web services or router status pages)
• Daemon mode for periodic checks, or integration with cron, PPP, and DHCP hooks
• Uses curl for network access (recommended and default in newer versions)
• Configuration via ddclient.conf with optional command-line overrides
• Supports environment-variable substitution in config for secrets (login/password)

Use Cases

• Keep a home server reachable via a domain name on a changing residential IP
• Automatically update DNS records for self-hosted services behind consumer ISPs
• Maintain IPv4/IPv6 address records for labs, small offices, or remote sites

Reliable and widely packaged across Unix-like systems, ddclient is a practical choice when you need automated DNS updates without running a full DNS stack. Its broad provider support and flexible IP detection make it suitable for many network environments.