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What is DDNS?

Dynamic DNS (DDNS) is the technology that lets you reliably reach a device even when its public IP address changes. Here's everything you need to understand how it works and why you need it.

The dynamic IP problem

When your device connects to the internet, your ISP assigns it a public IP address. For most home and small business connections, this IP is dynamic — it can change at any time: when your router reboots, when your ISP performs maintenance, or simply when your DHCP lease expires.

This creates a problem the moment you want to access your home network from outside — for example, to reach a file server, security camera, self-hosted application, or VPN. If you bookmark your IP address today and it changes tomorrow, the bookmark stops working and you have no way to reconnect without first discovering your new IP.

DDNS solves this problem by giving you a stable hostname that always points to your current IP — no matter how often it changes.

How DDNS works

DDNS works through three components working together: a DDNS provider, a client running on your network, and the DNS system.

DDNS client detects your IP

A lightweight program runs on your router or server. It periodically checks your current public IP address — either by querying a detection service or by reading it from your router's WAN interface.

Client calls the update API

When your IP changes (or on a regular schedule), the client sends an authenticated HTTP request to the DDNS provider's update endpoint — in NovaDNS's case, https://novadns.io/api/update.

Provider updates the DNS record

NovaDNS receives the update and immediately sets the A record (for IPv4) or AAAA record (for IPv6) for your hostname — for example, home.novaip.link — to your new IP address.

Other devices look up the hostname

Anything that needs to reach your device uses the hostname instead of the IP. Because the TTL is kept low (60 seconds), DNS changes propagate globally within about a minute.

From the perspective of anything connecting to your device, it simply uses a hostname like home.novaip.link and it always works — even after your IP has changed multiple times.

DNS records involved

NovaDNS manages two DNS record types for each hostname, updated automatically whenever the client reports a new address.

A

Maps your hostname to an IPv4 address (e.g. 203.0.113.42). Updated whenever your IPv4 changes.

AAAA

Maps your hostname to an IPv6 address (e.g. 2001:db8::1). Updated only when an IPv6 address is detected. Deleted if the client reports no IPv6.

All NovaDNS records are published with a TTL of 60 seconds. This means that after an IP change, the new address is visible globally within about one minute — far faster than standard DNS which can cache records for hours.

digexample DNS lookup

$ dig home.novaip.link A +short
203.0.113.42

$ dig home.novaip.link AAAA +short
2001:db8::1

DDNS vs static IP

A static IP is an address that never changes — your ISP assigns it permanently to your account. It sounds like the obvious solution, but there are significant drawbacks.

Static IPs typically cost $10–20 per month on top of your normal internet bill
Many ISPs — particularly residential ones — simply do not offer static IPs to home customers
Business-grade static IP packages often require a contract and a premises visit
You still need a domain name and DNS hosting to make the IP usable as a hostname

DDNS achieves the same end result — a stable, human-readable hostname that always reaches your device — for a fraction of the cost, and in most cases entirely for free. The 60-second TTL means updates propagate fast enough that, in practice, the brief changeover period during an IP change is unnoticeable.

Common use cases

DDNS is useful anywhere you need to reliably reach a device over the internet when you cannot control the IP address assigned to it.

Remote access to a home server — reach your Nextcloud, Plex, or Home Assistant from anywhere
VPN server — use your hostname as the WireGuard or OpenVPN endpoint
Security cameras — connect to your NVR or camera system from your phone
NAS (Network Attached Storage) — access your files remotely without a cloud subscription
Game servers — give friends a stable address to connect to your Minecraft, Valheim, or other server
Self-hosted web services — run your own website, API, or app without paying for a cloud VM
Remote desktop — RDP or VNC into your home PC from the office

Why NovaDNS?

There are several DDNS providers available, but NovaDNS is built for users who care about reliability, privacy, and a clean experience.

No ads, no trackersNovaDNS does not run ads or sell your data. The service is supported by straightforward paid plans.

Dedicated novaip.link domainYour hostnames live under novaip.link — a clean, dedicated domain that is not shared with unrelated services.

First-class IPv6 supportBoth A and AAAA records are managed automatically. IPv6 is supported on every plan including Free.

DynDNS compatibilityWorks with every router, NAS, and DDNS client out of the box. No plugins or scripts required for most devices.

Webhook eventsGet notified via HTTP webhook whenever a host's IP changes. Useful for automation, monitoring, and audit trails.

TeamsShare a workspace with your team on paid plans. Role-based access control keeps the right people in control.

Quick Start

API Reference

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