ddclient
ddclient is a Perl-based Dynamic DNS client that detects IP changes and updates DNS records across many supported DDNS and DNS provider APIs.

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.
