DNS Explained

What is DNS hosting (and why do you need it?)
The DNS (domain name system) is what makes web addresses like www.techstore.com actually work.
It relates the domain name to an IP address such as 193.111.200.100 –
the ‘real’ underlying address of the server.




So, as well as email hosting and web hosting, every website or email address also needs DNS hosting.
You don’t tend to hear so much about this, because it’s usually thrown in with one or more of the other services.

But once your setup moves beyond a simple website and hosted email setup,
DNS hosting is something you need to think about.

DNS hosting
Most Internet users rely on their ISP to manage their primary and secondary DNS on their behalf.
It’s definitely the simplest and easiest approach.

But it usually means less flexibility- you can’t always set up subdomains, create CNAME records,
or set up a backup location for email if your mail-server goes down.

When you need to manage DNS
When you need to set up subdomains like http://support.eurohostprol.com/, or point your MX (mail exchange) record at your mailserver, while hosting your website elsewhere, then it becomes useful to have your DNS hosted somewhere you can get at it.

Specialist DNS hosting services usually offer a web-based control panel (like hsphere), which allows you to edit your DNS records and set up your own custom zone files. Dynamic DNS services also allow the DNS configuration to be changed automatically.

Dynamic DNS
Why on earth would you need to be able to change your DNS dynamically? After all how often do you move your web hosting anyway?

Well, perhaps you’ve got a server connected to the Internet using an ADSL line, and it sometimes changes IP address. Many Internet service providers don’t offer static IP addresses, so your local mailserver, for example, won’t always have the same unique numerical identifier.

But to be really useful, your local mailserver should have a nice friendly domain name like home.domain.dom where users can always find it. Dynamic DNS lets you do this: whenever the IP address changes, so does the DNS.

Now, you can provide services even to relatively naïve users who might not be happy changing settings and checking for a new IP address if they are unable to connect.

We wouldn’t recommend this approach for a public website, but it could work well for an Intranet or a games server, as well as being very handy for local mailservers.

These are exactly the kind of situations where dynamic DNS hosting comes into its own.




How does Dynamic DNS work?
First, you need access to DNS servers where propagation is fast – so that when your changes have been submitted, they are made immediately available. Gradwell’s servers propagate changes within a few seconds, for example.

Then you need to be able to send a message to the DNS server with the current location of the server.

Dynamic DNS software such as Direct Update works by sending a message to the DNS server to update it on the current location of the server.

At gradwell dot com, we also have a system that allows you to update the DNS servers by making an http call.

So to update the DNS, all you need is your web browser and the correct web address (though if your IP addresses change regularly, we recommend using a script to make the http call automatically).

Thanks the Techstore Team