DNS should never hang on one server. This page counts the .dk domains whose nameservers share a single host, address, network or autonomous system, the single points of failure that turn one outage into a dead domain. Data comes from our own scanners, which re-resolve every .dk domain in the zone roughly once a week.
| Every nameserver is on… | Domains | Share | Why it matters |
|---|---|---|---|
| A single nameserver host | 153 | 0.01% | Any outage or mistake on that host takes the domain offline; RFC 1034 asks for at least two. |
| A single nameserver address | 1,310 | 0.11% | Several NS names, but they all resolve to one IP, so they are really one server. |
| One IPv4 /24 and no IPv6 | 10,687 | 0.90% | All nameservers share one network: a routing problem there takes them all down. |
| One autonomous system | 758,181 | 64.1% | Common and usually fine with a large provider, but one network outage still takes all nameservers down. |
| No IPv6 nameserver | 85,361 | 7.2% | IPv6-only resolvers cannot reach the zone. |
Click a row to list its domains (computed 2026-10-04 11:14).