Why you still see your old website after moving servers

This week we moved genzis.net to a new server. We updated the domain, deployed the new site, opened it in a browser… and saw the old website.

Nothing was broken. The new site was live. Some visitors already saw it, others still saw the old one, and our own laptop was one of the stubborn ones. If you have ever changed hosting and wondered why “it works for you but not for me”, this is why.

Your domain is a phone book entry

Computers don’t find websites by name, they find them by address: a number like 203.0.113.10. The DNS (Domain Name System) is the phone book that turns genzis.net into that number.

When you move to a new server, you don’t move the domain. You simply update its entry in the phone book so it points to the new address. That part takes seconds.

Everyone keeps a copy of the phone book

Looking up a name every single time would be slow, so everyone along the way keeps a copy of the answer for a while: your browser, your computer, your internet provider, your company’s network.

How long they keep it is decided by a setting on the record called the TTL (“time to live”). Ours was 14400 seconds, so four hours. Until that copy expires, a computer that recently visited the site keeps using the old address, and keeps showing the old site.

That is all “DNS propagation” really is. Nothing is spreading across the internet. Old copies are expiring, one by one.

How to check what people actually see

Ask a public resolver. Sites like dnschecker.org show the address your domain points to from different countries. If they all show the new one, the change is done.
Use your phone on mobile data. It uses a different network and a different cache than your office Wi-Fi.
On your computer, run nslookup yourdomain.com to see which address your machine is using.

In our case, the public resolvers already showed the new server while my laptop still answered with the old one. The fix was simply waiting, or clearing the local cache.

How to move a site without the confusion

Lower the TTL a day before the move, to 5 minutes (300). Copies then expire quickly when you switch.
Set up and test the new server first, using a temporary address your host gives you.
Switch the record, and keep the old server running for a day so nobody lands on an error page.
Raise the TTL again once everything is stable.

One thing not to break: email

Your domain’s phone book has separate entries for the website and for email (the MX records). Moving the website should only change the website’s entry. Before cancelling the old hosting, check where your mailboxes live. If they are on the old server, cancelling it stops your email, even though the website is fine.

We kept our email exactly where it was and only moved the website. The visitors never noticed; only our own laptop needed a little patience.

Planning a move to new hosting? Talk to us, it is the kind of thing we do every week.

Your domain is a phone book entry

Computers don’t find websites by name, they find them by address: a number like 203.0.113.10. The DNS (Domain Name System) is the phone book that turns genzis.net into that number.

When you move to a new server, you don’t move the domain. You simply update its entry in the phone book so it points to the new address. That part takes seconds.

Everyone keeps a copy of the phone book

Looking up a name every single time would be slow, so everyone along the way keeps a copy of the answer for a while: your browser, your computer, your internet provider, your company’s network.

That is all “DNS propagation” really is. Nothing is spreading across the internet. Old copies are expiring, one by one.

How to check what people actually see

Ask a public resolver. Sites like dnschecker.org show the address your domain points to from different countries. If they all show the new one, the change is done.

Use your phone on mobile data. It uses a different network and a different cache than your office Wi-Fi.

On your computer, run nslookup yourdomain.com to see which address your machine is using.

In our case, the public resolvers already showed the new server while my laptop still answered with the old one. The fix was simply waiting, or clearing the local cache.

How to move a site without the confusion

Lower the TTL a day before the move, to 5 minutes (300). Copies then expire quickly when you switch.

Set up and test the new server first, using a temporary address your host gives you.

Switch the record, and keep the old server running for a day so nobody lands on an error page.

Raise the TTL again once everything is stable.

One thing not to break: email

We kept our email exactly where it was and only moved the website. The visitors never noticed; only our own laptop needed a little patience.

Planning a move to new hosting? Talk to us, it is the kind of thing we do every week.