Care and timing are central to good domain name management

Less prominent uses of domain names

We tend to think of domain names mainly as website addresses, as with NS’s ns.nl. In practice, however, they’re also used as signposts to applications and systems. If a signpost is taken down, the application or system it pointed to can’t be found. In practice, that’s often the result of someone slipping up when making a change. The slip might be a typo in a manually entered IP address, for example, or a spelling mistake in a name server name. Or maybe a name server will be set up, pointing to a host that doesn’t yet exist.

Mis-managed update

In the NS case, it was a domain name transfer that went wrong. A transfer is an administrative procedure, where the responsibility for managing a domain name’s registration is moved from one service provider (.nl registrar) to another. A transfer doesn't have any effect on the working of the domain name. In this case, however, it seems that the domain name’s name server records were changed at the same time, before the new name servers had actually been set up.

Transfer

There’s a crucial difference between a domain name transfer and a name server change. In a transfer, it’s only the registrar looking after the domain name that changes. Although the domain name moves from registrar A to registrar B, the name’s technical configuration remains unaltered. That’s important, because the new registrar often needs a little time to arrange things.

Name server change

By contrast, a name server change involves changing the information recorded in the DNS about where to find the domain’s server. The change may be to the name servers themselves, or to the servers’ IP addresses. In either case, the effect of an error is the same: the DNS will direct internet users to a server that doesn’t actually know about the domain. With the result that the application linked to the domain name becomes unreachable.

It pays to take care

When making a name server change, therefore, it’s important to proceed carefully. Especially because, when a name server change is made, it has to be published online right across the internet. It can take up to 24 hours before all web servers around the world have picked up the new information and will direct users to the right name servers. And, if a mistake is made, that’s how long it’ll be before the corrected information about a .nl name server is available everywhere.

Timing

In order the minimise the risk, most organisations make changes of this kind at quiet times, when the systems in question are handling little or no traffic. Say, in the small hours at the weekend. Unfortunately, NS chose to make the switch during the Monday morning rush hour.

General advice

How can an organisation avoid problems when something needs changing? I have 2 pieces of general advice:

1. Make sure you have an overview

Many large organisations have numerous domain names and name servers, which they use for different things. Some visible (websites); some not (applications, systems). The less visible uses are sometimes overlooked when putting through changes, potentially with very unfortunate consequences. So make sure you have comprehensive, up-to-date records, and that you monitor the internet for ‘forgotten’ domain names.

2. Involve your service provider

The NS incident illustrates the importance of taking domain name changes and DNS updates very seriously. That goes not only for big organisations like NS, but also for anyone who depends on electronic services. It’s therefore important to involve your hosting service provider, .nl registrar or DNS service provider. After all, a DNS change is something that even the biggest organisation only needs to do once in a while. Whereas, for your service provider, it’s a practised everyday task.