Your website's address will change; its name must not. Dynamic DNS gives you a permanent hostname plus a tiny updater that rewrites its record every time your ISP hands you a new address. Set it up once, in the right place, and your site survives every change without you noticing.
✍️ Technical Anshu🪟 Windows 10 / 11⏱️ 8 minute read
🎥 Watch the video to see the Dynamic DNS hostname created and connected to the domain
Dynamic DNS is the beating heart of the hosting method in the video - it is what makes a static IP unnecessary. But most DDNS failures are not setup failures; they are discipline failures that appear weeks later, when an updater quietly stopped working and nobody checked. This guide covers both: the setup, and the habits that keep it true.
Anatomy of one Dynamic DNS update (example values)
Router reconnects, new WAN IP49.37.91.7
Updater notices and rewritesyourname.example-dns.com
DNS now answers49.37.91.7
Visitors noticenothing at all
1
What You Are Actually Creating
Three small things. A hostname - a name like yourname.example-dns.com (an example) under a DDNS provider's domain. An account with that provider, which owns the hostname. And an updater - software that logs in and rewrites the hostname's DNS record whenever your public IP changes. Most providers offer a free tier with a hostname or two, which is all home hosting needs. Your own domain later points at this hostname with a CNAME record, so the pretty name stays stable while this machinery moves underneath.
2
Put the Updater in the Router If You Possibly Can
The updater's job is to notice address changes, so put it where changes are seen first and where power never sleeps:
Router built-in DDNS (best). Most routers have a Dynamic DNS page listing supported providers. Enter the hostname and account once. The router updates the record the moment its WAN address changes - no PC needs to be awake.
Updater program on the PC (fallback). Fine when the router lacks your provider, but it only works while the PC is on, and it must be set to start with Windows. Acceptable here - the PC is the server - but it is one more moving part.
Whichever you choose, use one updater. Two updaters with the same account can fight and leave the record flapping between addresses.
3
Prove It Works Before You Trust It
Look up your hostname: nslookup yourname.example-dns.com - the answer should equal your current public IP.
Restart the router and let the ISP hand you a new address.
Within a few minutes, run the same lookup again. The answer must have followed. If it has, the system works; if not, you have found a setup mistake while it is still cheap.
If the provider lets you choose a TTL, keep it low - in the few-hundred-seconds range - so the world's DNS caches forget old answers quickly after each change.
4
The Failure Modes Nobody Warns Beginners About
The expiring free account. Some free DDNS tiers ask you to confirm the hostname periodically or log in now and then. Miss it, and the name silently stops resolving.
The changed password. You update the DDNS account password, the router keeps trying the old one, and the record freezes at the last address - no error is shown anywhere a beginner would look.
The router reset. A firmware update or factory reset wipes the DDNS page along with everything else.
The cure is a one-minute monthly habit: open your own site from your phone on mobile data. If it loads, every layer - DDNS included - is alive.
5
Dynamic DNS Is Not a Tunnel - Know What It Does Not Do
DDNS fixes the address problem only. Your ports still face the internet directly, so the safety rules (only 80 and 443 forwarded, patched server, strong admin logins) apply in full. And if your ISP has placed you behind CGNAT, DDNS cannot rescue the setup at all - the record will faithfully point at an address the internet cannot knock on. That case belongs to the tunnel route, and the companion CGNAT guide shows the two-minute check that tells you which road you are on.
🎥 Watch the Complete Process in the Video
Watch the video to see the DDNS hostname created, the updater configured and the domain connected, all live.
Most providers run a free tier with one or a few hostnames, and home hosting needs exactly one. Paid tiers mostly add more hostnames and remove the periodic confirmation chore. A custom domain, if you want one, is a separate small yearly cost at a registrar.
How quickly does the record follow a new IP?
The updater usually reacts within minutes of the change. Visitors may still be sent to the old address until their DNS cache expires - with a low TTL that is minutes, not hours. A brief wobble after an address change is normal; a site still dead the next morning is a broken updater.
DDNS is set up, but the site still dies whenever the IP changes. Why?
Almost always the updater is not running: the router DDNS page got disabled by a reset, the PC updater is not starting with Windows, or the account password changed. Verify with nslookup right after a router restart - the record must show the new address. If it shows the old one, you have found your culprit.
This guide is based on the Technical Anshu home website hosting video • Stuck on any step? Ask in the video comments — you will get a reply there 🙏